FORM 6 - K

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Private Issuer

Pursuant to Rule 13a - 16 or 15d - 16 of

the Securities Exchange Act of 1934

As of September 1, 2009

TENARIS, S.A.

(Translation of Registrant's name into English)

TENARIS, S.A.

46a, Avenue John F. Kennedy

L-1855 Luxembourg

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or 40-F.

Form 20-F  ü    Form 40-F

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12G3-2(b) under the Securities Exchange Act of 1934.

Yes  No ü

If “Yes” is marked, indicate below the file number assigned to the registrant in connection

with Rule 12g3-2(b): 82-

The attached material is being furnished to the Securities and Exchange Commission pursuant to Rule 13a-16 and Form 6-K under the Securities Exchange Act of 1934, as amended. This report contains Tenaris's half-year report.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: September 1, 2009

Tenaris, S.A.

By: /s/ Cecilia Bilesio

Cecilia Bilesio

Corporate Secretary

TENARIS S.A.

HALF-YEAR REPORT 2009

­NY12527:166450.2

TABLE OF CONTENTS

INTERIM MANAGEMENT REPORT	2
Company OVERVIEW	4
PRINCIPAL RISKS AND UNCERTAINTIES	5
business overview	7
Related Party Transactions	14
MANAGEMENT CERTIFICATION	15
FINANCIAL INFORMATION	16
Consolidated Condensed Interim Financial Statements	16
CORPORATE INFORMATION	36
Investor information	36

Tenaris S.A.  Half-year report 2009-Interim management report

Interim Management Report

·   CERTAIN DEFINED TERMS

Unless otherwise specified or if the context so requires:

·   References in this half-year report to “the Company” refer exclusively to Tenaris S.A., a Luxembourg joint stock corporation (société anonyme holding).

·   References in this half-year report to “Tenaris”, “we”, “us” or “our” refer to Tenaris S.A. and its consolidated subsidiaries.

·   References in this half-year report to “San Faustin” refer to San Faustin N.V., a Netherlands Antilles corporation and the Company’s controlling shareholder.

·   “Shares” refers to ordinary shares, par value $1.00 of the Company.

·   “ADSs” refers to the American Depositary Shares, which are evidenced by American Depositary Receipts.

·   “tons” refers to metric tons; one metric ton is equal to 1,000 kilograms, 2,204.62 pounds, or 1.102 U.S. (short) tons.

·   “billion” refers to one thousand million, or 1,000,000,000.

·   “dollars”, “U.S. dollars”, “US$” or “$” each refers to the United States dollar.

·   PRESENTATION OF CERTAIN FINANCIAL AND OTHER INFORMATION

Accounting Principles

We prepare our consolidated financial statements in conformity with International Financial Reporting Standards, or IFRS, as issued by the International Accounting Standards Board, or IASB, and adopted by the European Union.

We publish consolidated financial statements expressed in U.S. dollars. The unaudited consolidated condensed interim financial statements included in this half-year report have been prepared in accordance with IAS 34, “Interim Financial Reporting”. These unaudited consolidated condensed interim financial statements should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2008, which have been prepared in accordance with IFRS, as issued by the IASB and adopted by the European Union.  See Note 2 “Accounting Policies and Basis of Presentation” to our unaudited consolidated condensed interim financial statements included in this half-year report.

The unaudited consolidated condensed interim financial statements included in this half-year report have been reviewed by PricewaterhouseCoopers through Price Waterhouse & Co. S.R.L., for purposes of complying with the requirements of the different jurisdictions where the Company is publicly listed.

Rounding

Certain monetary amounts, percentages and other figures included in this half-year report have been subject to rounding adjustments. Accordingly, figures shown as totals in certain tables may not be the arithmetic aggregation of the figures that precede them, and figures expressed as percentages in the text may not total 100% or, as applicable, when aggregated may not be the arithmetic aggregation of the percentages that precede them.

·   CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS

This half-year report and any other oral or written statements made by us to the public may contain “forward-looking statements”. Forward looking statements are based on management’s current views and assumptions and involve known and unknown risks that could cause actual results, performance or events to differ materially from those expressed or implied by those statements.

We use words such as “aim”, “will likely result”, “will continue”, “contemplate”, “seek to”, “future”, “objective”, “goal”, “should”, “will pursue”, “anticipate”, “estimate”, “expect”, “project”, “intend”, “plan”, “believe” and words and terms of similar substance to identify forward-looking statements, but they are not the only way we identify such statements. This half-year report contains forward-looking statements, including with respect to certain of our plans and current goals and expectations relating to Tenaris’s future financial condition and performance. Sections of this half-year report that by their nature contain forward-looking statements include, but are not limited to, “Principal Risks and Uncertainties”, and “Operating and Financial Review and Prospects”. In addition to the risks related to our business discussed under “Principal Risks and Uncertainties”, other factors could cause actual results to differ materially from those described in the forward-looking statements. These factors include, but are not limited to:

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Tenaris S.A.  Half-year report 2009-Interim management report

·   our ability to implement our business strategy or to grow through acquisitions, joint ventures and other investments;

·   our ability to price our products and services in accordance with our strategy;

·   trends in the levels of investment in oil and gas exploration and drilling worldwide;

·   general macroeconomic and political conditions in the countries in which we operate or distribute pipes; and

·   our ability to absorb cost increases and to secure supplies of essential raw materials and energy.

By their nature, certain disclosures relating to these and other risks are only estimates and could be materially different from what actually occurs in the future. As a result, actual future gains or losses that may affect our financial condition and results of operations could differ materially from those that have been estimated. You should not place undue reliance on the forward-looking statements, which speak only as of the date of this half-year report. Except as required by law, we are not under any obligation, and expressly disclaim any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or otherwise.

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Tenaris S.A.  Half-year report 2009-Interim management report

COMPANY OVERVIEW

We are a leading global manufacturer and supplier of steel pipe products and related services for the world’s energy industry as well as for other industrial applications. Our customers include most of the world’s leading oil and gas companies as well as engineering companies engaged in constructing oil and gas gathering, transportation and processing facilities. Our principal products include casing, tubing, line pipe, and mechanical and structural pipes.

In the last fifteen years, we have expanded our business globally through a series of strategic investments, and, in the last three years, we have transformed our presence in the North American market through the acquisitions of Maverick, a leading North American producer of steel pipe products for the oil and gas industry with operations in the U.S., Canada and Colombia, and Hydril, a leading North American manufacturer of premium connections for steel pipe products used in the oil and gas industry with an established reputation worldwide. We now operate an integrated worldwide network of steel pipe manufacturing, research, finishing and service facilities with industrial operations in North and South America, Europe, Asia and Africa and a direct presence in most major oil and gas markets.

Our business is organized in three business segments: Tubes, Projects, and Others.

·   Tubes includes our operations that consist in the production, distribution and sale of seamless and welded tubular products and related services mainly for energy and select industrial applications.

·   Projects includes our operations that consist in the production, distribution and sale of welded pipes mainly used in the construction of major pipeline projects.

·   Others includes our operations that consist mainly in the production, distribution and sale of sucker rods, welded steel pipes for electric conduits, industrial equipment and raw materials, such as hot briquetted iron, or HBI, that exceed our internal requirements.

For more information on the Company, including its competitive strengths, business segments and products see our annual report for the year ended December 31, 2008, and for a discussion and analysis of our of our financial condition and results of operations see “Business overview - Operating and Financial Review and Prospects” in this half-year report.

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Tenaris S.A.  Half-year report 2009-Interim management report

PRINCIPAL RISKS AND UNCERTAINTIES

We face certain risks associated to our business and the industry in which we operate. We are a global steel pipe manufacturer with a strong focus on manufacturing products and related services for the oil and gas industry. Demand for our products depends primarily on the level of exploration, development and production activities of oil and gas companies which is affected by current and expected future prices of oil and natural gas.  Several factors, such as the supply and demand for oil and gas, and political and global economic conditions, affect these prices. The recent worldwide financial and credit crisis that caused the current economic downturn may negatively affect our business and could have a material adverse effect on our revenues, profitability and financial position. For example, the current global economic crisis has resulted in a significant decline in oil and gas prices, which affected the level of drilling activity, triggered efforts to reduce inventories and thus reduced demand for our products and services. Similarly, our sales of steel pipe products for pipeline projects depend mainly on the implementation of major regional projects, which are likely to be adversely affected by changes in governmental policies, the impact of the credit crisis on our customers’ ability to perform their payment obligations with us and any adverse economic, political or social developments in our major markets. In turn, increases in the cost of raw materials and energy may hurt our profitability if we are not able to recover them through increased prices of our products.

We have significant operations in various countries, including Argentina, Brazil, Canada, Colombia, Italy, Japan, Mexico, Romania and the United States, and we sell our products and services throughout the world. Therefore, like other companies with worldwide operations, we are exposed to risks from fluctuations in foreign currency exchange rates, interest rates and inflation, governmental policies regarding spending, exchange controls, regulatory and taxation changes, and other adverse political, economic or social developments in such countries, which could affect our revenues, profitability and financial condition. As a global company, a portion of our business is carried out in currencies other than the U.S. dollar, which is the Company’s functional currency. As a result, we are exposed to foreign exchange rate risk, which could adversely affect our financial position and results of operations.

On May 22, 2009, Venezuela’s President Hugo Chávez announced the nationalization of Tavsa, Matesi and Comsigua. The Company’s investments in Tavsa, Matesi and Comsigua are protected under applicable bilateral investment treaties, including the bilateral investment treaty between Venezuela and the Belgian-Luxembourgish Union, and Tenaris continues to reserve all of its rights under contracts, investment treaties and Venezuelan and international law, and to consent to the jurisdiction of the ICSID in connection with the nationalization process. However, we can give no assurance that the Venezuelan government will agree to pay a fair and adequate compensation for our interest in Tavsa, Matesi and Comisigua, or that any such compensation will be freely convertible into or exchangeable for foreign currency. We may be forced to engage in litigation procedures to enforce our rights under contracts, investment treaties and Venezuelan and international law, and the time, costs and management efforts associated with such litigation may be significant. For further information on the nationalization of the Venezuelan subsidiaries, see “Business overview -Main events of the semester – Developments in Venezuela” in this half-year report and Note 14 “Processes in Venezuela” to our unaudited consolidated condensed interim financial statements included in this half-year report.

A key element of our business strategy is to develop and offer higher value-added products and services and to continuously identify and pursue growth-enhancing strategic opportunities. Failure to successfully implement our strategy or to integrate future acquisitions and strategic partnerships could affect our ability to grow, our competitive position and our sales and profitability. In addition, failure to agree with our joint venture partner in Japan on the strategic direction of our joint operations, may have an adverse impact on our operations in Japan.

At December 31, 2008, we had $1,890.6 million in goodwill and intangible assets with indefinite useful life, which are exposed to impairment tests and correspond mainly to the acquisition of Maverick ($772.0 million) and Hydril ($919.9 million). In 2008 we recorded an impairment charge for $502.9 million (of which $394.3 million correspond to Maverick); however, we can give no assurance that further impairment charges will not be required in the future.

Potential environmental, product liability and other claims arising from the inherent risks associated with the products we sell and the services we render, including well failures, line pipe leaks, bursts and fires, that could result in death, personal injury, property damage, environmental pollution or loss of production could create significant liabilities for us. In addition, we are subject to a wide range of local, provincial and national laws, regulations, permit requirements and decrees relating to the protection of human health and the environment and the cost of complying with such regulations as well as unforeseen environmental liabilities may increase our operating costs or negatively impact our net worth.  Similarly, we conduct business in certain countries known to experience governmental corruption.  Although we are committed to conducting business in a legal and ethical manner in compliance with local and international statutory requirements and standards applicable to our business, there is a risk that our employees or representatives may take actions that violate applicable laws and regulations that generally prohibit the making of improper payments to foreign government officials for the purpose of obtaining or keeping business, including laws relating to the 1997 OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions such as the U.S. Foreign Corrupt Practices Act.

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Tenaris S.A.  Half-year report 2009-Interim management report

As a holding company, our ability to pay expenses, debt service and cash dividends depends on the results of operations and financial condition of our subsidiaries, which could be restricted by legal, contractual or other limitations, including exchange controls or transfer restrictions, and other agreements and commitments of our subsidiaries.

The Company’s controlling shareholder may be able to take actions that do not reflect the will or best interests of other shareholders.

The Company’s tax-exempt status will terminate on December 31, 2010. If we are unable to mitigate the consequences of the termination of the preferential tax regime applying to the Company, we may be subject to a higher tax burden in the future and our shareholders may be subject to tax withholdings.

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Tenaris S.A.  Half-year report 2009-Interim management report

BUSINESS OVERVIEW

Operating and Financial Review and Prospects

The following discussion and analysis should be read in conjunction with the audited consolidated financial statements and the related notes included in our annual report for the year ended December 31, 2008, and is based on, and should be read in conjunction with, the unaudited consolidated condensed interim financial statements for the six-month period ended June 30, 2009, included in this half-year report.

Certain information contained in this discussion and analysis and presented elsewhere in this half-year report, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. See “Cautionary Statement Concerning Forward-Looking Statements” in this half-year report. In evaluating this discussion and analysis, you should specifically consider the various risk factors identified in “Principal Risks and Uncertainties”, other risk factors identified elsewhere in this half-year report and other factors that could cause results to differ materially from those expressed in such forward-looking statements.

Market Background and Outlook

Following their collapse in the second half of 2008 to a low of around $40 per barrel at the end of the year, global oil prices have risen during the first half of 2009 and have reached the level of $60-70 per barrel. This reflects increased optimism for a recovery in global economic growth led by China together with an expected decline in non-OPEC production and ongoing OPEC actions to cut production. North American gas prices, however, have fallen during the first half of 2009 to current levels of around $3.00 per million BTU as the carry over increases of 2008 U.S. production combined with reduced demand has resulted in high levels of gas in storage.

The international count of active drilling rigs, as published by Baker Hughes, continued to decline during the first semester of 2009, averaging 1,004 during such period, 8% lower than the second semester and 6% lower than the first semester of 2008. The corresponding rig count in the U.S., which is more sensitive to North American gas prices, fell sharply in the first half of the year and at June 2009, was down 56% from its high in September 2008 but since July 2009, has shown signs of stabilizing. It averaged 1,131 during the first semester of 2009, 42% lower than the second semester and 38% lower than the first semester of 2008. In Canada, the corresponding rig count, which is affected by seasonal drilling patterns, averaged 210 during the first semester of 2009, a decrease of 38% compared to the first semester of 2008.

Demand for our pipes from the global energy industry has been affected by the decline in oil and gas drilling activity and the actions taken by customers to adjust to reduced cash flows and a less favorable market outlook, including procurement delays and cancellations and the postponement of new project activity. Demand in the U.S. and Canada has been further affected by extraordinarily high levels of OCTG inventories. Demand for pipes from the industrial and power generation segments remain at low levels.

We expect shipments for our large-diameter pipes for pipeline projects in South America, in the second half of the year, to remain close to the levels shown during the first half, however the order backlog continues to decline as new projects are postponed.

Steel and steelmaking raw material costs have stabilized and in recent weeks have shown some increase. However our costs, particularly at our North American welded pipe operations, will continue to be adversely affected by low production levels and the high cost of raw material inventories procured under different market conditions, partially offset by the actions taken to reduce our structural costs.

With low levels of demand likely to persist until the end of the year and prices adjusting downwards we expect that our sales and operating income will be lower in the second half of the year than the first. We expect that there will be a recovery in our shipments going into 2010 but that our revenues may not recover to the same extent considering the lagged effect of price declines in our results.

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Tenaris S.A.  Half-year report 2009-Interim management report

Results of Operations

Unaudited Consolidated condensed interim income statement

(all amounts in thousands of U.S. dollars, unless otherwise stated)	Six-month period  ended June 30,
Continuing operations	2009						2008
				%						%
Net sales		4,530,632			100.0			5,710,424			100.0
Cost of sales		(2,628,211	)		(58.0	)		(3,302,831	)		(57.8	)
Gross profit		1,902,421			42.0			2,407,593			42.2
Selling, general and administrative expenses		(783,006	)		(17.3	)		(878,038	)		(15.4	)
Other operating income (expense), net		3,024			0.1			(4,947	)		(0.1	)
Operating income		1,122,439			24.8			1,524,608			26.7
Interest income		12,737			0.3			28,681			0.5
Interest expense		(63,582	)		(1.4	)		(100,124	)		(1.8	)
Other financial results		(52,266	)		(1.2	)		(9,572	)		(0.2	)
Income before equity in earnings of associated companies and income tax		1,019,328			22.5			1,443,593			25.3
Equity in earnings of associated companies		57,935			1.3			97,963			1.7
Income before income tax		1,077,263			23.8			1,541,556			27.0
Income tax		(319,592	)		(7.1	)		(428,464	)		(7.5	)
Income for continuing operations		757,671			16.7			1,113,092			19.5
Discontinued operations
Result for discontinued operations		(28,138	)		(0.6	)		416,906			7.3
Income for the period		729,533			16.1			1,529,998			26.8
Attributable to:
Equity holders of the Company		709,315			15.7			1,460,514			25.6
Minority interest		20,218			0.4			69,484			1.2
		729,533			16.1			1,529,998			26.8

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Tenaris S.A.  Half-year report 2009-Interim management report

Selected consolidated financial position data

Thousands of U.S. dollars (except number of shares)	June 30,		December 31,
	2009		2008
Current assets		(1)6,037,734		7,252,417
Property, plant and equipment, net		3,122,122		2,982,871
Other non-current assets		4,644,218		4,865,424
Total assets		13,804,074		15,100,712
Current liabilities		2,440,999		3,790,017
Non-current borrowings		998,251		1,241,048
Deferred tax liabilities		867,000		1,053,838
Other non-current liabilities		291,253		313,922
Total liabilities		4,597,503		6,398,825
Capital and reserves attributable to the Company’s equity holders		8,637,036		8,176,571
Minority interest		569,535		525,316
Total liabilities and equity		13,804,074		15,100,712
Number of shares outstanding		1,180,536,830		1,180,536,830

(1) At June 30, 2009, current assets include assets available for sale amounting to $21.6 million.

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Tenaris S.A.  Half-year report 2009-Interim management report

Six-month period ended June 30, 2009, compared to six-month period ended June 30, 2008

Summary

Net income attributable to equity holders in the Company during the first semester of 2009 was $709.3 million, or $0.60 per share ($1.20 per ADS), which compares with net income attributable to equity holders in the Company during the first semester of 2008 of $1,460.5 million, or $1.24 per share ($2.47 per ADS). Operating income was $1,122.4 million, or 25% of net sales during the first semester of 2009, compared to $1,524.6 million, or 27% of net sales during the fist semester of 2008. Operating income plus depreciation and amortization for this semester was $1,370.5 million, or 30% of net sales, compared to $1,789.3 million, or 31% of net sales during the first semester of 2008.

During the quarter, we re-presented the results of our Venezuelan operations that are in the process of being nationalized as discontinued operations.

Net Sales, Cost of Sales and Operating Income by segment

The following table shows our net sales by business segment for the periods indicated below:

Millions of U.S. dollars	For the six-month period ended June 30,
	2009				2008				Increase / (Decrease)
Tubes		3,809.4	84	%		4,681.2	82	%		(19	%)
Projects		476.6	11	%		639.8	11	%		(26	%)
Others		244.7	5	%		389.4	7	%		(37	%)
Total		4,530.6	100	%		5,710.4	100	%		(21	%)

The following table indicates our sales volume of seamless and welded pipes by business segment for the periods indicated below:

Thousands of tons	For the six-month period ended June 30,
	2009		2008		Increase / (Decrease)
Tubes – Seamless		1,076		1,457		(26	%)
Tubes – Welded		175		552		(68	%)
Tubes – Total		1,251		2,009		(38	%)
Projects – Welded		174		302		(42	%)
Total – Tubes + Projects		1,424		2,311		(38	%)

Tubes

The following table indicates, for our Tubes business segment, net sales by geographic region, cost of sales as a percentage of net sales, operating income and operating income as a percentage of net sales for the periods indicated below:

Millions of U.S. dollars	For the six-month period ended June 30,
	2009			2008			Increase / (Decrease)
Net sales
- North America		1,676.8			1,819.1			(8	%)
- South America		494.3			528.8			(7	%)
- Europe		484.9			928.4			(48	%)
- Middle East & Africa		848.0			1,041.3			(19	%)
- Far East & Oceania		305.4			363.7			(16	%)
Total net sales		3,809.4			4,681.2			(19	%)
Cost of sales (% of sales)		55	%		55	%
Operating income		1,026.3			1,342.0			(24	%)
Operating income (% of sales)		27	%		29	%

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Tenaris S.A.  Half-year report 2009-Interim management report

Net sales of tubular products and services decreased 19% to $3,809.4 million in the first half of 2009, compared to $4,681.2 million in the first half of 2008, due to a sharp reduction in volumes, which was partially offset by higher average selling prices, reflecting in part a higher proportion of sales of specialized high-end products.

Cost of sales of tubular products and services, expressed as a percentage of net sales, remained stable at 55%.

Operating income from tubular products and services decreased 24% to $1,026.3 million in the first half of 2009, from $1,342.0 million in the first half of 2008, mainly due to the reduction in sales. Operating income expressed as a percentage of net sales decreased to 27% in the first half of 2009, compared to 29% in the first half of 2008, mainly due to the effect of fixed and semi-fixed selling, general and administrative expenses, over lower revenues.

Projects

The following table indicates, for our Projects business segment, net sales, cost of sales as a percentage of net sales, operating income and operating income as a percentage of net sales for the periods indicated below:

Millions of U.S. dollars	For the six-month period ended June 30,
	2009			2008			Increase / (Decrease)
Net sales		476.6			639.8			(26	%)
Cost of sales (% of sales)		72	%		71	%
Operating income		94.5			128.9			(27	%)
Operating income (% of sales)		20	%		20	%

Net sales of pipes for pipeline projects decreased 26% to $476.6 million in the first half of 2009, compared to $639.8 million in the first half of 2008, reflecting lower deliveries in Brazil and Argentina to gas and other pipeline projects.

Operating income from pipes for pipeline projects decreased 27% to $94.5 million in the first half of 2009, from $128.9 million in the first half of 2008, mainly in line with the decline in revenues, and as a percentage of net sales it remained stable at 20%.

Others

The following table indicates, for our Others business segment, net sales, cost of sales as a percentage of net sales, operating income and operating income as a percentage of net sales for the periods indicated below:

Millions of U.S. dollars	For the six-month period ended June 30,
	2009			2008			Increase / (Decrease)
Net sales		244.7			389.4			(37	%)
Cost of sales (% of sales)		84	%		72	%
Operating income		1.6			53.7			(97	%)
Operating income (% of sales)		1	%		14	%

Net sales of other products and services decreased 37% to $244.7 million in the first half of 2009, compared to $389.4 million in the first half of 2008, mainly reflecting lower sales of welded pipes for electric conduits in the U.S. and sucker rods.

Operating income from other products and services decreased 97% to $1.6 million in the first half of 2009, compared to $53.7 million during the first half of 2008, mainly due to recorded losses on our electric conduits operations in the U.S.

Selling, general and administrative expenses, or SG&A, increased as a percentage of net sales to 17.3% in the semester ended June 30, 2009, compared to 15.4% in the corresponding semester of 2008, mainly due to the effect of fixed and semi-fixed expenses over lower revenues.

Net interest expensesdecreased to$50.8 million in the first half of 2009, compared to $71.4 million in the same period of 2008 reflecting a lower net debt position and lower interest rates.

Other financial resultsrecorded a loss of $52.3 million during the first half of 2009, compared to a loss of $9.6 million during the first half of 2008. These results largely reflect gains and losses on net foreign exchange transactions and the fair value of derivative instruments and are partially offset by changes to our net equity position. These gains and losses are mainly attributable to variations in the exchange rates between our subsidiaries’ functional currency (other than the U.S. dollar) and the U.S. dollar, in accordance with IFRS.

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Tenaris S.A.  Half-year report 2009-Interim management report

Equity in earnings of associated companiesgenerated a gain of $57.9 million in the first half of 2009, compared to a gain of $98.0 million in the first half of 2008. These gains were derived mainly from our equity investment in Ternium.

Income taxcharges totaled $319.6 million in the first half of 2009, equivalent to 31% of income before equity in earnings of associated companies and income tax, compared to $428.5 million in the first half of 2008, equivalent to 30% of income before equity in earnings of associated companies and income tax.

Income from discontinued operationsamounted to a loss of $28.1 million in the first half of 2009 corresponding to our Venezuelan operations that are being nationalized, compared to a gain of $416.9 million in the corresponding period of 2008, of which $394.3 million corresponded to the result of the sale of Hydril’s pressure control business. See Note 12 “Discontinued Operations” to our unaudited consolidated condensed interim financial statements included in this half-year report.

Income attributable to minority interestamounted to $20.2 million in the first half of 2009, compared to $69.5 million in the corresponding semester of 2008, mainly reflecting lower results at NKKTubes and at our Venezuelan subsidiaries.

Liquidity and Capital Resources

The following table provides certain information related to our cash generation and changes in our cash and cash equivalents position for the periods indicated below:

Millions of U.S. dollars	For the six-month period ended June 30,
	2009			2008
Net cash provided by operating activities		1,874.6			842.9
Net cash (used in) provided by investing activities		(511.9	)		661.2
Net cash (used in) financing activities		(1,267.0	)		(1,252.9	)
Increase in cash and cash equivalents		95.7			251.2
Cash and cash equivalents at the beginning of year		1,525.0			954.3
Effect of exchange rate changes		(2.3	)		113.6
(Decrease) due to deconsolidation		(9.7	)		-
Increase in cash and cash equivalents		95.7			251.2
Cash and cash equivalents at period end		1,608.7			1,319.0

Net cash provided by operations during the first half of 2009 was $1.9 billion, compared to $842.9 million in the first half of 2008. Working capital decreased by $1.2 billion during the semester, as we reduced our inventories by $940.6 million and trade receivables by $586.3 million, which was partially offset by a decrease in trade payables $365.2 million.

Capital expenditures amounted to $226.3 million in the first half of 2009, compared to $205.4 million in the first half of 2008.

During the first half of 2009, total financial debt decreased by $1.0 billion to $2.0 billion at June 30, 2009 from $3.0 billion at December 31, 2008. Net financial debt (total financial debt less cash and other current investments) decreased by $1.3 billion in the first half of 2009, to $0.1 billion at June 30, 2009, from $1.4 billion at December 31, 2008.

12

Tenaris S.A.  Half-year report 2009-Interim management report

Main Events of the Semester

Acquisition of Seamless Pipe Indonesia Jaya

In April 2009, we acquired from Bakrie & Brothers TbK, Green Pipe International Limited and Cakrawala Baru a 77.45% holding in Seamless Pipe Indonesia Jaya, or SPIJ, an Indonesian OCTG processing business with heat treatment and premium connection threading facilities, for a purchase price of $69.5 million, with $21.9 million payable as consideration for SPIJ’s equity and $47.6 million payable as consideration for the assignment of certain sellers’ loan to SPIJ. SPIJ has an annual processing capacity of 120,000 tons and has had a commercial alliance with us for more than a decade. SPIJ employs around 500 persons and had revenues of approximately $140 million in 2008.

Developments in Venezuela

Sidor Nationalization Process

On June 30, 2009, the Company held 11.46% of the capital stock of Ternium S.A.

On May 7, 2009, Ternium completed the transfer of its entire 59.7% interest in Sidor to CVG. The transfer was effected as a result of Venezuela’s Decree Law 6058, which ordered that Sidor and its subsidiaries and associated companies be transformed into state-owned enterprises and declared the activities of such companies of public and social interest. While CVG had assumed operational control of Sidor on July 12, 2008, Ternium had retained formal title over the shares until May 7, 2009. Ternium agreed to receive an aggregate amount of $1.97 billion as compensation for its Sidor shares. Of that amount, CVG paid $400 million in cash on May 7, 2009. The balance was divided in two tranches: the first tranche, of $945 million, will be paid in six equal quarterly installments, while the second tranche will be paid at maturity in November 2010, subject to quarterly mandatory prepayment events based on the increase of the WTI crude oil price over its May 6, 2009 level.

Nationalization of Venezuelan Subsidiaries

Within the framework of Decree Law 6058, on May 22, 2009, Venezuela’s President Hugo Chávez announced the nationalization of, among other companies, the Company’s majority-owned subsidiaries TAVSA – Tubos de Acero de Venezuela S.A. (“Tavsa”) and, Matesi, Materiales Siderurgicos S.A (“Matesi”), and Complejo Siderurgico de Guayana, C.A (“Comsigua”), in which the Company has a minority interest (collectively, “the Venezuelan Companies”). On May 25, 2009, the Minister of Basic Industries and Mines of Venezuela (“MIBAM”) issued official communications N°230/09 and 231/09, appointing the MIBAM’s representatives to the transition committees charged with overseeing the nationalization processes of Tavsa and Matesi. On May 29, 2009, the Company sent response letters to the MIBAM acknowledging the Venezuelan government’s decision to nationalize Tavsa and Matesi, appointing its representatives to the transition committees, and reserving all of its rights under contracts, investment treaties and Venezuelan and international law and the right to submit any controversy between the Company or its subsidiaries and Venezuela relating to Tavsa and Matesi’s nationalization to international arbitration, including arbitration administered by ICSID.

On July 14, 2009, President Chávez issued Decree 6796, which orders the acquisition of the Venezuelan Companies and provides that Tavsa will be held by the Ministry of Energy and Oil, while Matesi and Comsigua will be held by MIBAM. Decree 6796 also requires the Venezuelan government to create certain committees at each of the Venezuelan Companies; each transition committee must ensure the nationalization of each Venezuelan Company and the continuity of its operations, and each technical committee (to be composed of representatives of Venezuela and the private sector) must negotiate over a 60-day period (extendable by mutual agreement) a fair price for each Venezuelan Company to be transferred to Venezuela. In the event the parties fail to reach agreement by the expiration of the 60-day period (or any extension thereof), the applicable Ministry will assume control and exclusive operation of the relevant Venezuelan Company, and the Executive Branch will order its expropriation in accordance with the Venezuelan Expropriation Law. The Decree also specifies that all facts and activities there under are subject to Venezuelan law and any disputes relating thereto must submitted to Venezuelan courts.

On August 19, 2009, we announced that Venezuela, acting through the transition committee appointed by the Venezuelan Ministry of Basic Industries and Mining, unilaterally assumed exclusive operational control over Matesi. While continuing to reserve all of its rights under investment treaties and Venezuelan and international law, Tenaris is prepared to engage in discussions with the Venezuelan government regarding the fair and adequate terms and conditions for the transfer of Matesi to Venezuela.

The Company’s investments in Tavsa, Matesi and Comsigua are protected under applicable bilateral investment treaties, including the bilateral investment treaty between Venezuela and the Belgian-Luxembourgish Union, and, as noted above, Tenaris continues to reserve all of its rights under contracts, investment treaties and Venezuelan and international law, and to consent to the jurisdiction of the ICSID in connection with the nationalization process. For further information on the nationalization of the Venezuelan subsidiaries, see Note 14 “Processes in Venezuela” to our unaudited consolidated condensed interim financial statements included in this half-year report.

13

Tenaris S.A.  Half-year report 2009-Interim management report

Annual General Meeting of Shareholders

On June 3, 2009, the Annual General Meeting of shareholders of the Company approved all resolutions on its agenda.  Among other resolutions adopted at the meeting, the shareholders approved the consolidated financial statements and annual accounts for the year ended December 31, 2008, as well as the payment of an annual dividend of $0.43 per share ($0.86 per ADS), or approximately $507 million. The amount approved includes the interim dividend previously paid in November 2008, in the amount of $0.13 per share ($0.26 per ADS). The balance of the annual dividend amounting to $0.30 per share ($0.60 per ADS), or approximately $354 million, was paid on June 25, 2009, with an ex-dividend date of June 22, 2009.

In addition, the Annual General Meeting of shareholders re-elected the then current members of the board of directors to serve until the next annual shareholders meeting (to be held in June 2010); and re-appointed PricewaterhouseCoopers as Tenaris’s independent auditors for the 2009 fiscal year.

The Annual General Meeting of shareholders also resolved to authorize the Company and the Company’s subsidiaries to acquire shares of the Company, including shares represented by ADSs, at such times and on such other terms and conditions as may be determined by the board of directors of the Company or the board of directors or other governing body of the relevant Company subsidiary.

For more information on the Annual General Meeting of Shareholders held on June 3, 2009, see the minutes of such meeting available on our website at http://www.tenaris.com/investors/.

RELATED PARTY TRANSACTIONS

Tenaris is a party to several related party transactions, which include, among others, purchases and sales of goods (including steel pipes, flat steel products, steel bars, raw materials, gas and electricity) and services (including engineering services and related services) from or to entities controlled by San Faustin or in which San Faustin holds significant interests. Material related party transactions are subject to the review of the audit committee of the Company’s board of directors and the requirements of the Company’s articles of association and Luxembourg law. For further detail on Tenaris’s related party transactions, see Note 13 “Related party transactions” to our unaudited consolidated condensed interim financial statements included in this half-year report.

14

Tenaris S.A.  Half-year report 2009-Management certification

Management Certification

We confirm, to the best of our knowledge, that:

1.   the unaudited consolidated condensed interim financial statements prepared in conformity with International Financial Reporting Standards included in this half year report, give a true and fair view of the assets, liabilities, financial position and profit or loss of Tenaris S.A. and its consolidated subsidiaries, taken as a whole; and

2.   the interim management report included in this half year report, includes a fair review of the important events that have occurred during the six-month period ended June 30, 2009, and their impact on the unaudited consolidated condensed interim financial statements for such period, material related party transactions and a description of the principal risks and uncertainties they face.

/s/ Paolo Rocca

Chief Executive Officer

Paolo Rocca

August 31, 2009

/s/ Ricardo Soler

Chief Financial Officer

Ricardo Soler

August 31, 2009

15

Tenaris S.A.  Half-year report 2009-Consolidated Condensed Interim Financial Statements

Financial Information

CONSOLIDATED CONDENSED INTERIM FINANCIAL

 STATEMENTS

Six-month period ended June 30, 2009

16

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

Report of Independent Registered Public Accounting Firm

To the Board of Directors and Shareholders of

Tenaris S.A.

We have reviewed the accompanying consolidated condensed interim statement of financial position of Tenaris S.A. and its subsidiaries as of June 30, 2009, and the related consolidated condensed interim statements of income and of comprehensive income for each of the three-month and six-month periods ended June 30, 2009 and 2008, and the consolidated condensed interim statements of changes in equity and of cash flows for the six-month periods ended June 30, 2009 and 2008. These consolidated condensed interim financial statements are the responsibility of the Company’s management.

We conducted our review in accordance with the standards of the Public Company Accounting Oversight Board (United States). A review of interim financial information consists principally of applying analytical procedures and making inquiries of persons responsible for financial and accounting matters. It is substantially less in scope than an audit conducted in accordance with the standards of the Public Company Accounting Oversight Board (United States), the objective of which is the expression of an opinion regarding the financial statements taken as a whole. Accordingly, we do not express such an opinion.

Based on our review, we are not aware of any material modifications that should be made to the accompanying consolidated condensed interim financial statements for them to be in conformity with International Accounting Standard 34 “Interim Financial Reporting” as issued by the International Accounting Standards Board and adopted by the European Union.

We previously audited in accordance with the standards of the Public Company Accounting Oversight Board (United States), the consolidated balance sheet as of December 31, 2008, and the related consolidated statements of income, of changes in equity and of cash flows for the year then ended (not presented herein); and in our report dated February 25, 2009, we expressed an unqualified opinion on those consolidated financial statements. In our opinion, the information set forth in the accompanying consolidated condensed statement of financial position as of December 31, 2008, is fairly stated in all material respects in relation to the consolidated balance sheet from which it has been derived.

 Buenos Aires, August 5, 2009

 PRICE WATERHOUSE & CO. S.R.L.

 by /s/ Diego M. Niebuhr

 (Partner)                                      

 Diego M. Niebuhr

17

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

CONSOLIDATED CONDENSED INTERIM INCOME STATEMENT

(all amounts in thousands of U.S. dollars, unless otherwise stated)		Three-month period ended June 30,		Six-month period ended June 30,
	Notes	2009	2008	2009	2008
Continuing operations		(Unaudited)		(Unaudited)
Net sales	3	2,096,344	3,110,103	4,530,632	5,710,424
Cost of sales	3 & 4	(1,264,899)	(1,820,717)	(2,628,211)	(3,302,831)
Gross profit		831,445	1,289,386	1,902,421	2,407,593
Selling, general and administrative expenses	3 & 5	(395,926)	(469,669)	(783,006)	(878,038)
Other operating income (expense), net	3	1,278	(3,708)	3,024	(4,947)
Operating income		436,797	816,009	1,122,439	1,524,608
Interest income	6	8,163	16,493	12,737	28,681
Interest expense	6	(24,435)	(33,962)	(63,582)	(100,124)
Other financial results	6	(15,907)	4,235	(52,266)	(9,572)
Income before equity in earnings of associated companies and income tax		404,618	802,775	1,019,328	1,443,593
Equity in earnings of associated companies		66,514	48,102	57,935	97,963
Income before income tax		471,132	850,877	1,077,263	1,541,556
Income tax		(114,518)	(219,339)	(319,592)	(428,464)
Income for continuing operations		356,614	631,538	757,671	1,113,092
Discontinued operations
Result for discontinued operations	12	(20,176)	398,497	(28,138)	416,906
Income for the period		336,438	1,030,035	729,533	1,529,998
Attributable to:
Equity holders of the Company		343,268	987,471	709,315	1,460,514
Minority interest		(6,830)	42,564	20,218	69,484
		336,438	1,030,035	729,533	1,529,998
Earnings per share attributable to the equity holders of the Company during year
Weighted average number of outstanding ordinary shares (thousands)	7	1,180,537	1,180,537	1,180,537	1,180,537
Earnings per share (U.S. dollars per share)	7	0.29	0.84	0.60	1.24
Earnings per ADS (U.S. dollars per ADS)	7	0.58	1.67	1.20	2.47

18

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

CONSOLIDATED CONDENSED INTERIM STATEMENT OF COMPREHENSIVE INCOME

(all amounts in thousands of U.S. dollars, unless otherwise stated)	Three-month period ended June 30,					Six-month period ended June 30,
	2009		2008			2009			2008
	(Unaudited)					(Unaudited)
Income for the period		336,438		1,030,035			729,533			1,529,998
Other comprehensive income:
Currency translation adjustment		295,277		72,355			161,862			176,272
Cash flow hedges		3,169		(8,294	)		(8,349	)		(6,365	)
Share of other comprehensive income of associates
Currency translation adjustment		12,093		17,137			(4,430	)		20,481
Cash flow hedges		1,176		(296	)		1,815			(296	)
Income tax relating to components of other comprehensive income		180		4,023			2,876			4,023
Other comprehensive income for the period, net of tax		311,895		84,925			153,774			194,115
Total comprehensive income for the period		648,333		1,114,960			883,307			1,724,113
Attributable to:
Equity holders of the Company		592,430		1,058,717			815,388			1,613,624
Minority interest		55,903		56,243			67,919			110,489
		648,333		1,114,960			883,307			1,724,113

The accompanying notes are an integral part of these Consolidated Condensed Interim Financial Statements. These Consolidated Condensed Interim Financial Statements should be read in conjunction with our audited Consolidated Financial Statements and notes for the fiscal year ended December 31, 2008.

19

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

CONSOLIDATED CONDENSED INTERIM STATEMENT OF FINANCIAL POSITION

(all amounts in thousands of U.S. dollars)		At June 30, 2009			At December 31, 2008
	Notes	(Unaudited)
ASSETS
Non-current assets
Property, plant and equipment, net	8		3,122,122			2,982,871
Intangible assets, net	9		3,736,821			3,826,987
Investments in associated companies			575,628			527,007
Other investments			29,488			38,355
Deferred tax assets			217,686			390,323
Receivables			84,595	7,766,340		82,752	7,848,295
Current assets
Inventories			2,150,785			3,091,401
Receivables and prepayments			228,791			251,481
Current tax assets			203,244			201,607
Trade receivables			1,536,984			2,123,296
Available for sale assets	14		21,572			-
Other investments			273,450			45,863
Cash and cash equivalents			1,622,908	6,037,734		1,538,769	7,252,417
Total assets				13,804,074			15,100,712
EQUITY
Capital and reserves attributable to the Company’s equity holders				8,637,036			8,176,571
Minority interest				569,535			525,316
Total equity				9,206,571			8,701,887
LIABILITIES
Non-current liabilities
Borrowings			998,251			1,241,048
Deferred tax liabilities			867,000			1,053,838
Other liabilities			209,365			223,142
Provisions			79,470			89,526
Trade payables			2,418	2,156,504		1,254	2,608,808
Current liabilities
Borrowings			1,019,972			1,735,967
Current tax liabilities			333,638			610,313
Other liabilities			247,478			242,620
Provisions			51,385			28,511
Customer advances			256,922			275,815
Trade payables			531,604	2,440,999		896,791	3,790,017
Total liabilities				4,597,503			6,398,825
Total equity and liabilities				13,804,074			15,100,712

Contingencies, commitments and restrictions to the distribution of profits are disclosed in Note 10.

The accompanying notes are an integral part of these Consolidated Condensed Interim Financial Statements. These Consolidated Condensed Interim Financial Statements should be read in conjunction with our audited Consolidated Financial Statements and notes for the fiscal year ended December 31, 2008.

20

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

CONSOLIDATED CONDENSED INTERIM STATEMENT OF CHANGES IN EQUITY

(all amounts in thousands of U.S. dollars)

	Attributable to equity holders of the Company
	Share Capital		Legal Reserves		Share Premium		Currency Translation Adjustment			Other Reserves			Retained Earnings (*)			Total			Minority Interest			Total
																						(Unaudited)
Balance at January 1, 2009		1,180,537		118,054		609,733		(223,779	)		2,127			6,489,899			8,176,571			525,316			8,701,887
Income for the period		-		-		-		-			-			709,315			709,315			20,218			729,533
Other comprehensive income por the period		-		-		-		106,799			(726	)		-			106,073			47,701			153,774
Total comprehensive income por the period		-		-		-		106,799			(726	)		709,315			815,388			67,919			883,307
Acquisition and decrease of minority interest		-		-		-		-			(783	)		-			(783	)		3,476			2,693
Change in equity reserves		-		-		-		-			21			-			21			-			21
Dividends paid in cash		-		-		-		-			-			(354,161	)		(354,161	)		(27,176	)		(381,337	)
Balance at June 30, 2009		1,180,537		118,054		609,733		(116,980	)		639			6,845,053			8,637,036			569,535			9,206,571

	Attributable to equity holders of the Company
	Share Capital		Legal Reserves		Share Premium		Currency Translation Adjustment		Other Reserves		Retained Earnings			Total			Minority Interest			Total
																				(Unaudited)
Balance at January 1, 2008		1,180,537		118,054		609,733		266,049		18,203		4,813,701			7,006,277			523,573			7,529,850
Income for the period		-		-		-		-		-		1,460,514			1,460,514			69,484			1,529,998
Other comprehensive income por the period		-		-		-		150,986		2,124		-			153,110			41,005			194,115
Total comprehensive income por the period		-		-		-		150,986		2,124		1,460,514			1,613,624			110,489			1,724,113
Acquisition and decrease of minority interest		-		-		-		-		-		-			-			(1,865	)		(1,865	)
Dividends paid in cash		-		-		-		-		-		(295,134	)		(295,134	)		(55,136	)		(350,270	)
Balance at June 30, 2008		1,180,537		118,054		609,733		417,035		20,327		5,979,081			8,324,767			577,061			8,901,828

(*) Retained Earnings as of December 31, 2008 calculated in accordance with Luxembourg Law are disclosed in Note 10.

The accompanying notes are an integral part of these Consolidated Condensed Interim Financial Statements. These Consolidated Condensed Interim Financial Statements should be read in conjunction with our audited Consolidated Financial Statements and notes for the fiscal year ended December 31, 2008.

21

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

CONSOLIDATED CONDENSED INTERIM STATEMENT OF CASH FLOWS

		Six-month period ended June 30,
(all amounts in thousands of U.S. dollars)	Note	2009			2008
Cash flows from operating activities		(Unaudited)			(Unaudited)
Income for the period			729,533			1,529,998
Adjustments for:
Depreciation and amortization	8 & 9		248,061			268,873
Income tax accruals less payments			(329,690	)		89,747
Equity in earnings of associated companies			(57,073	)		(98,096	)
Income from the sale of pressure control business			-			(394,323	)
Interest accruals less payments, net			(23,698	)		(7,894	)
Changes in provisions			14,200			15,243
Changes in working capital			1,175,460			(545,614	)
Other, including currency translation adjustment			117,792			(15,017	)
Net cash provided by operating activities			1,874,585			842,917
Cash flows from investing activities
Capital expenditures	8 & 9		(226,335	)		(205,366	)
Acquisitions of subsidiaries and minority interest	11		(73,535	)		(1,865	)
Proceeds from the sale of pressure control business (*)	12		-			1,113,805
Proceeds from disposal of property, plant and equipment and intangible assets			10,328			8,826
Investments in short terms securities			(227,587	)		(264,401	)
Dividends received			5,223			13,636
Other			-			(3,428	)
Net cash (used in) provided by investing activities			(511,906	)		661,207
Cash flows from financing activities
Dividends paid			(354,161	)		(295,134	)
Dividends paid to minority interest in subsidiaries			(27,176	)		(55,136	)
Proceeds from borrowings			263,841			430,088
Repayments of borrowings			(1,149,484	)		(1,332,755	)
Net cash used in financing activities			(1,266,980	)		(1,252,937	)
Increase in cash and cash equivalents			95,699			251,187
Movement in cash and cash equivalents
At the beginning of the period			1,525,022			954,303
Effect of exchange rate changes			(2,330	)		113,559
Decrease due to deconsolidation			(9,696	)		-
Increase in cash and cash equivalents			95,699			251,187
At June 30,			1,608,695			1,319,049
		At June 30,
Cash and cash equivalents		2009			2008
Cash and bank deposits			1,622,908			1,337,838
Bank overdrafts			(14,213	)		(18,789	)
			1,608,695			1,319,049

(*) Includes $394 million of after-tax gain, $381 million of assets and liabilities held for sale and $339 million of income tax charges and related expenses.

The accompanying notes are an integral part of these Consolidated Condensed Interim Financial Statements. These Consolidated Condensed Interim Financial Statements should be read in conjunction with our audited Consolidated Financial Statements and notes for the fiscal year ended December 31, 2008.

22

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

NOTES TO THE CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS

1	General information
2	Accounting policies and basis of presentation
3	Segment information
4	Cost of sales
5	Selling, general and administrative expenses
6	Financial results
7	Earnings and dividends per share
8	Property, plant and equipment, net
9	Intangible assets, net
10	Contingencies, commitments and restrictions on the distribution of profits
11	Business combinations and other acquisitions
12	Discontinued operations
13	Related party transactions
14	Processes in Venezuela

23

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

NOTES TO THE CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS

(In the notes all amounts are shown in U.S. dollars, unless otherwise stated)

1 General information

Tenaris S.A. (the “Company”), a Luxembourg corporation (societé anonyme holding), was incorporated on December 17, 2001 as a holding company in steel pipe manufacturing and distributing operations. The Company holds, either directly or indirectly, controlling interests in various subsidiaries. References in these Consolidated Condensed Interim Financial Statements to “Tenaris” refer to Tenaris S.A. and its consolidated subsidiaries. A list of the principal Company’s subsidiaries is included in Note 31 to the audited Consolidated Financial Statements for the year ended December 31, 2008.

These Consolidated Condensed Interim Financial Statements were approved for issue by the Company’s Board of Directors on August 5, 2009.

2 Accounting policies and basis of presentation

These Consolidated Condensed Interim Financial Statements have been prepared in accordance with IAS 34, “Interim Financial Reporting”. These Consolidated Condensed Interim Financial Statements should be read in conjunction with the audited Consolidated Financial Statements for the year ended December 31, 2008, which have been prepared in accordance with International Financial Reporting Standards (“IFRS”) as issued by the International Accounting Standard Board and adopted by the European Union.

Considering the comments described below, the accounting policies used in the preparation of these Consolidated Condensed Interim Financial Statements are consistent with those used in the audited Consolidated Financial Statements for the year ended December 31, 2008.

The following standards’ amendment is mandatory for the financial year beginning 1 January, 2009:

IAS 1 (revised), “Presentation of financial statements”: The revised standard prohibits the presentation of items of income and expenses (that is “non-owner changes in equity”) in the statement of changes in equity, requiring them to be presented separately from owner changes in equity. Entities can choose whether to present one performance statement (the statement of comprehensive income) or two statements (the income statement and the statement of comprehensive income). The Company has elected to present two statements: an income statement and a statement of comprehensive income. These interim financial statements have been prepared under the revised disclosure requirements.

Certain comparative amounts have been reclassified to conform to changes in presentation in the current year.

The preparation of Consolidated Condensed Interim Financial Statements in conformity with IFRS requires management to make certain accounting estimates and assumptions that might affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the balance sheet dates, and the reported amounts of revenues and expenses for the reported periods. Actual results may differ from these estimates.

Material inter-company transactions, balances and unrealized gains (losses) on transactions between Tenaris subsidiaries have been eliminated in consolidation. However, since the functional currency of some subsidiaries is its respective local currency, some financial gains (losses) arising from inter-company transactions are generated. These are included in the Consolidated Condensed Interim Income Statement under Other financial results.

24

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

3           Segment information

Reportable operating segments

 (Unaudited)

(all amounts in thousands of U.S. dollars)	Tubes	Projects	Other	Total Continuing operations	Total Discontinued operations (*)
Six-month period ended June 30, 2009
Net sales	3,809,353	476,624	244,655	4,530,632	18,558
Cost of sales	(2,077,069)	(345,108)	(206,034)	(2,628,211)	(31,866)
Gross profit	1,732,284	131,516	38,621	1,902,421	(13,308)
Selling, general and administrative expenses	(707,979)	(38,476)	(36,551)	(783,006)	(9,540)
Other operating income (expenses), net	2,002	1,458	(436)	3,024	(179)
Operating income	1,026,307	94,498	1,634	1,122,439	(23,027)
Depreciation  and amortization	227,226	8,381	12,427	248,034	27
Six-month period ended June 30, 2008
Net sales	4,681,221	639,848	389,355	5,710,424	162,536
Cost of sales	(2,564,622)	(456,549)	(281,660)	(3,302,831)	(98,481)
Gross profit	2,116,599	183,299	107,695	2,407,593	64,055
Selling, general and administrative expenses	(773,278)	(54,067)	(50,693)	(878,038)	(27,431)
Other operating income (expenses), net	(1,308)	(316)	(3,323)	(4,947)	409
Operating income	1,342,013	128,916	53,679	1,524,608	37,033
Depreciation and amortization	242,715	10,432	11,501	264,648	13,190

Geographical information

 (Unaudited)

(all amounts in thousands of U.S. dollars)	North America	South America	Europe	Middle East & Africa	Far East & Oceania	Total Continuing operations	Total Discontinued operations (*)
Six-month period ended June 30, 2009
Net sales	1,744,014	1,125,490	507,205	848,525	305,398	4,530,632	18,558
Depreciation and amortization	137,582	48,123	52,543	622	9,164	248,034	27
Six-month period ended June 30, 2008
Net sales	1,994,333	1,309,551	1,000,841	1,041,299	364,400	5,710,424	162,536
Depreciation and amortization	151,081	50,076	55,958	621	6,912	264,648	13,190

(*) Corresponds to pressure control operations and the nationalization Venezuelan subsidiaries.

Allocation of net sales to geographical information is based on customer location. Allocation of depreciation and amortization is based on the geographical location of the underlying assets.

There are no revenues from external customers attributable to the Company’s country of incorporation (Luxembourg). For geographical information purposes, “North America” comprises principally Canada, Mexico and the USA; “South America” comprises principally Argentina, Brazil, Colombia, Venezuela, Peru and Ecuador; “Europe” comprises principally Italy and Norway; “Middle East and Africa” comprises principally Egypt and Saudi Arabia; “Far East and Oceania” comprises principally China, Indonesia and Japan.

25

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

4           Cost of sales

	Six-month period ended June 30,
(all amounts in thousands of U.S. dollars)	2009			2008
	(Unaudited)
Inventories at the beginning of the period		3,091,401			2,598,856
Plus: Charges of the period
Raw materials, energy, consumables and other		981,233			2,825,458
Increase in inventory due to business combinations		53,541			-
Services and fees		123,894			204,830
Labor cost		346,720			463,678
Depreciation of property, plant and equipment		126,330			144,107
Amortization of intangible assets		1,257			1,061
Maintenance expenses		82,756			105,953
Provisions for contingencies		1,374			12
Allowance for obsolescence		20,614			(10,259	)
Taxes		3,576			4,953
Other		21,892			54,513
		1,763,187			3,794,306
Transfer to assets available for sale		(43,726	)		-
Less: Inventories at the end of the period		(2,150,785	)		(2,991,850	)
		2,660,077			3,401,312
From Discontinued operations		(31,866	)		(98,481	)
		2,628,211			3,302,831

5           Selling, general and administrative expenses

	Six-month period ended June 30,
(all amounts in thousands of U.S. dollars)	2009			2008
	(Unaudited)
Services and fees		106,450			108,024
Labor cost		220,461			221,264
Depreciation of property, plant and equipment		5,517			6,402
Amortization of intangible assets		114,957			126,268
Commissions, freight and other selling expenses		208,554			283,484
Provisions for contingencies		16,346			15,632
Allowances for doubtful accounts		10,094			4,881
Taxes		59,275			77,928
Other		50,892			61,586
		792,546			905,469
From Discontinued operations		(9,540	)		(27,431	)
		783,006			878,038

26

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

6           Financial results

(all amounts in thousands of U.S. dollars)	Six-month period ended June 30,
	2009			2008
	(Unaudited)
Interest income		12,892			29,020
Interest expense		(67,162	)		(102,285	)
Interest net		(54,270	)		(73,265	)
Net foreign exchange transaction results and changes in fair value of derivative instruments (*)		(49,688	)		(5,714	)
Other		(3,460	)		(7,430	)
Other financial results		(53,148	)		(13,144	)
Net financial results		(107,418	)		(86,409	)
From Discontinued operations		4,307			5,394
		(103,111	)		(81,015	)

Each comparative item included in this note differs from its corresponding line in the Consolidated Condensed Interim Income Statement because it includes discontinued operations’ results.

Net foreign exchange transaction results include those amounts that affect the gross margin of certain subsidiaries which functional currencies are different from the U.S. dollar.

(*) Tenaris has identified certain embedded derivatives and in accordance with IAS 39 (“Financial Instruments: Recognition and Measurement”) has accounted them separately from their host contracts. Results arising from the valuation of these contracts have been recognized under “Net foreign exchange transaction results and changes in fair value of derivative instruments”.

7           Earnings and dividends per share

Earnings per share are calculated by dividing the net income attributable to equity holders of the Company by the daily weighted average number of ordinary shares in issue during the period.

	Six-month period ended June 30,
	2009			2008
	(Unaudited)
Income attributable to equity holders		709,315			1,460,514
Weighted average number of ordinary shares in issue (thousand)		1,180,537			1,180,537
Basic and diluted earnings per share ( U.S. dollars per share)		0.60			1.24
Basic and diluted earnings per ADS ( U.S. dollars per ADS) (*)		1.20			2.47
Result for discontinued operations		(28,138	)		416,906
Basic and diluted earnings per share		(0.02	)		0.35
Basic and diluted earnings per ADS (*)		(0.05	)		0.71

(*) Each ADS equals to two shares

On June 3, 2009, the Company’s shareholders approved an annual dividend in the amount of $0.43 per share ($0.86 per ADS). The amount approved included the interim dividend previously paid in November 2008, in the amount of $0.13 per share ($0.26 per ADS). The balance, amounting to $0.30 per share ($0.60 per ADS), was paid on June 25, 2009. In the aggregate, the interim dividend paid in November 2008 and the balance paid in June 2009 amounted to approximately $507 million.

27

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

8           Property, plant and equipment, net

(all amounts in thousands of U.S. dollars)	2009			2008
	(Unaudited)
Six-month period ended June 30,
Opening net book amount		2,982,871			3,269,007
Currency translation differences		47,637			125,124
Increase due to business combinations		24,123			-
Additions		217,169			185,440
Disposals		(9,782	)		(7,338	)
Transfers		(1,989	)		(906	)
Depreciation charge		(131,847	)		(148,255	)
Disposals due to deconsolidation		(6,060	)		-
At June 30,		3,122,122			3,423,072

9           Intangible assets, net

(all amounts in thousands of U.S. dollars)	2009			2008
	(Unaudited)
Six-month period ended June 30,
Opening net book amount		3,826,987			4,542,352
Currency translation differences		15,869			(13,592	)
Additions		9,166			19,926
Disposals		(546	)		(1,488	)
Transfers		1,989			906
Amortization charge		(116,214	)		(120,618	)
Disposals due to deconsolidation		(430	)		-
At June 30,		3,736,821			4,427,486

10           Contingencies, commitments and restrictions to the distribution of profits

Contingencies

This note should be read in conjunction with Note 26 to the Company’s audited Consolidated Financial Statements for the year ended December 31, 2008.

Asbestos-related litigation

Dalmine S.p.A. (“Dalmine”), a Tenaris subsidiary organized in Italy is currently subject to 12 civil proceedings for work-related injuries arising from the use of asbestos in its manufacturing processes during the period from 1960 to 1980. In addition, another 30 asbestos related out-of-court claims have been forwarded to Dalmine.

As of June 30, 2009, the total claims pending against Dalmine were 42 (of which, none are covered by insurance): during the six month period ended June 30, 2009, 7new claims were filed, noclaims were adjudicated, and 5 claims were settled out of which 4 were paid, 3claim were rejected, and 13 claims were dismissed.

Aggregate settlement costs to date for Tenaris are Euro 8.0 million ($11.3 million). Dalmine estimates that its potential liability in connection with the claims not yet settled is approximately Euro 12.2million ($17.3 million).

Accruals for Dalmine’s potential liability are based on the average of the amounts paid by Dalmine for asbestos related claims plus an additional amount related to some reimbursements requested by the social security authority. The maximum potential liability is not determinable as in some cases the requests for damages do not specify amounts, and instead is to be determined by the court. The timing of payment of the amounts claimed is not presently determinable.

28

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

Maverick litigation

On November 22, 2006, Maverick Tube Corporation (“Maverick”) received a letter from The Bank of New York as trustee (“the Trustee”) for the holders of 2004 4% Convertible Senior Subordinated Notes due 2033 issued by Maverick (“the 2004 Notes”), concerning an alleged breach of the indenture entered into on December 30, 2004, between Maverick and the Trustee, and governing the 2004 Notes (as amended, the “Indenture”). The alleged breach of the Indenture was based on Maverick’s refusal to grant the holders of the 2004 Notes conversion rights provided by the “Public Acquirer Change of Control” provision of the Indenture.

On December 11, 2006 the Trustee filed a complaint against Maverick and Tenaris in the United States District Court for the Southern District of New York. The complaint alleges that Tenaris’s acquisition of Maverick triggered the “Public Acquirer Change of Control” provision and asserted a breach of contract claim against Maverick for refusing to accept the 2004 Notes for conversion for the consideration specified in the “Public Acquirer Change of Control” provision. The complaint also seeks a declaratory judgment that Tenaris’s acquisition of Maverick was a “Public Acquirer Change of Control” under the Indenture and therefore triggers the above mentioned conversion rights, and asserts claims for tortuous interference with contract and unjust enrichment against Tenaris.

Defendants filed a motion to dismiss the complaint, or in the alternative, for summary judgment on March 13, 2007. Plaintiff filed a motion for partial summary judgment on the same date. On January 25, 2008, Law Debenture Trust Company of New York, (as successor to The Bank of New York as trustee under the Indenture) was substituted for The Bank of New York as plaintiff. On October 15, 2008, the court denied Law Debenture’s motion for partial summary judgment and granted defendants’ motion for summary judgment dismissing the complaint in its entirety. On November 20, 2008, Law Debenture filed a notice of appeal in the United States Court of Appeals for the Second Circuit. Law Debenture’s opening brief on appeal was filed on March 30, 2009, the brief for Maverick and Tenaris was filed on May 28, 2009 and Law Debenture’s reply brief was filed on June 28, 2009. The case has not yet been scheduled for oral arguments.

Tenaris believes that these claims are without merit. Accordingly, no provision was recorded in these Consolidated Condensed Interim Financial Statements. Were plaintiff to prevail, Tenaris estimates that the recovery would be approximately $50 million, plus interest.

Conversion of tax loss carry-forwards

On December 18, 2000, the Argentine tax authorities notified Siderca S.A.I.C., a Tenaris subsidiary organized in Argentina (“Siderca”), of an income tax assessment related to the conversion of tax loss carry-forwards into Debt Consolidation Bonds under Argentine Law No. 24.073. The adjustments proposed by the tax authorities represent an estimated contingency of ARS87 million (approximately $23 million) at June 30, 2009, in taxes and penalties. Based on the views of Siderca’s tax advisors, Tenaris believes that it is not probable that the ultimate resolution of the matter will result in an obligation. Accordingly, no provision was recorded in these Consolidated Condensed Interim Financial Statements.

Customer Claim

A lawsuit was filed on September 6, 2007, against three Tenaris’ subsidiaries, alleging negligence, gross negligence and intentional acts characterized as fraudulent inducement concerning allegedly defective well casing. Plaintiff alleged the complete loss of one natural gas production well and formation damage that precludes further exploration and production at the well site and sought compensatory and punitive damages of $25 million. The lawsuit was subsequently amended to add the Company and other of its subsidiaries as defendants and to change the claims to be breach of contract and fraud. On October 22, 2008, the Plaintiff again amended its petition to add new counts (including strict liability) and increase its prayer for damages to $245 million, plus punitive damages, treble damages and attorney fees. Each petition was tendered to a Tenaris subsidiary insurer, and the Tenaris subsidiary received the insurer’s agreement to provide a defense. The insurer reserved its rights with respect to its indemnity obligations and made an offer for coverage that the Tenaris subsidiary considers insufficient. On July 20, 2009 the lawsuit was settled for an amount of $15 million and thus a Tenaris subsidiary recorded a provision of $12.7 million in addition to the previously recorded of $2.3 million and according to IAS 37, no expected reimbursement from the insurer has been registered yet. As of the date of these Consolidated Condensed Interim Financial Statements, the insurer is not participating in this settlement, and the Tenaris subsidiary has initiated legal proceedings against the insurer.

29

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

Ongoing investigation

The Company has learned from one of its customers in Central Asia that certain sales agency payments made by one of the Company’s subsidiaries may have improperly benefited employees of the customer and other persons. These payments may have violated certain applicable laws, including the U.S. FCPA. The Audit Committee of the Company’s Board of Directors has engaged external counsel in connection with a review of these payments and related matters, and the Company has voluntarily notified the U.S. Securities and Exchange Commission and the U.S. Department of Justice. The Company will share the results of this review with the appropriate regulatory agencies, and will cooperate with any investigations that may be conducted by such agencies. At this time, the Company cannot predict the outcome of these matters or estimate the range of potential loss or extent of risk, if any, to the Company’s business that may result from resolution of these matters.

Commitments

Set forth is a description of Tenaris’s main outstanding commitments:

·   A Tenaris company is a party to a five-year contract with Nucor Corporation, under which it committed to purchase from Nucor steel coils, with deliveries starting in January 2007 on a monthly basis. As a result of current global downturn and the lower level of steel coil purchases planned for future months, the Tenaris company has negotiated and obtained from Nucor a waiver of the monthly committed volumes. The Company is reviewing its steel purchasing requirements with Nucor each quarter, therefore, the current waiver of monthly commitments is valid until September 30, 2009.

·   A Tenaris company is a party to a ten-year raw material purchase contract with QIT, under which it committed to purchase steel bars, with deliveries starting in July 2007. The estimated aggregate amount of the contract at current prices is approximately $277.7 million. The contract allows the Tenaris company to claim lower commitments in market downturns and severe market downturns subject to certain limitations.

·   A Tenaris company is a party to a contract with SMS Meer GmbH for the purchase of equipment, engineering, training and other services related to the equipment for an outstanding amount of approximately EUR84.7 (approximately $119.7 million). The Tenaris company may terminate the contract at any time paying a cancellation fee in the amount of EUR48.0 million (approximately $67.8 million).

·   A Tenaris company is a party to transportation capacity agreements with Transportadora de Gas del Norte S.A. for purchasing capacity of 1,000,000 cubic meters per day until 2017. As of June 30, 2009, the outstanding value of this commitment was approximately $29.2 million. The Tenaris company also expects to obtain additional gas transportation capacity of 315,000 cubic meters per day until 2027. This additional commitment is subject to completion of the enlargement of certain pipelines in Argentina.

·   A Tenaris company is a party to a contract with Siderar for the supply of steam generated at the power generation facility owned by Tenaris in San Nicolas, Argentina. Under this contract, the Tenaris company is required to provide 250 tn/hour of steam and Siderar has the obligation to take or pay this volume. The contract terminates in 2018.

Restrictions to the distribution of profits and payment of dividends

As of December 31, 2008, shareholders' equity as defined under Luxembourg law and regulations consisted of:

30

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

(all amounts in thousands of U.S. dollars)                                                                                                                     

Share capital	1,180,537
Legal reserve	118,054
Share premium	609,733
Retained earnings including net income for the year ended December 31, 2008	3,174,932
Total shareholders equity in accordance with Luxembourg law	5,083,256

At least 5% of the Company’s net income per year, as calculated in accordance with Luxembourg law and regulations, must be allocated to the creation of a legal reserve equivalent to 10% of the Company’s share capital. As of December 31, 2008, this reserve is fully allocated and additional allocations to the reserve are not required under Luxembourg law. Dividends may not be paid out of the legal reserve.

The Company may pay dividends to the extent, among other conditions, that it has distributable retained earnings calculated in accordance with Luxembourg law and regulations.

At December 31, 2008, retained earnings and result for the financial period of Tenaris under Luxembourg law totals $3.2billion, as detailed below.

(all amounts in thousands of U.S. dollars)                                                                                                                     

Retained earnings at December 31, 2007 under Luxembourg law	2,399,973
Dividends received	1,338,868
Other income and expenses for the year ended December 31, 2008	(115,305)
Dividends paid	(448,604)
Retained earnings at December 31, 2008 under Luxembourg law	3,174,932

11           Business combinations and other acquisitions

(a) Tenaris acquired control of Seamless Pipe Indonesia Jaya

In April 2009, Tenaris completed the acquisition from Bakrie & Brothers TbK, Green Pipe International Limited and Cakrawala Baru of a 77.45% holding in Seamless Pipe Indonesia Jaya (“SPIJ”), an Indonesian OCTG processing business with heat treatment and premium connection threading facilities, for a purchase price of $69.5 million, with $21.9 million being payable as consideration for SPIJ's equity and $47.6 million as consideration for the assignment of certain sellers' loan to SPIJ. Tenaris began consolidating SPIJ’s balance sheet and results of operations since its acquisition date.

11           Business combinations and other acquisitions  (Cont.)

(b) Minority Interest

During the six-month period ended June 30, 2009, additional shares of Confab and Dalmine were acquired from minority shareholders for approximately $9.5 million.

The assets and liabilities provisionally determined arising from the acquisitions are as follows:

	Six month period ended June 30, 2009
Other assets and liabilities (net)		(1,309	)
Property, plant and equipment		24,123
Net assets acquired		22,814
Minority interest		3,121
Sub-total		25,935
Assumedliabilities		47,600
Sub-total		73,535
Cash-acquired		5,501
Purchase consideration		79,036

31

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

The businesses acquired as of June 30, 2009 contributed revenues of $33.0 million and an operating income of $1.2million.

12           Discontinued operations

Nationalization of Venezuelan Subsidiaries

The results of operations and cash flows generated by the Venezuelan Companies are presented as discontinued operations in these Consolidated Condensed Interim Financial Statements. For further information see Note 14.

 Sale of Hydril pressure control business

On April 1, 2008, Tenaris sold to General Electric Company (GE) the pressure control business included as part of the acquisition of Hydril Company undertaken on May 2007. The pressure control business was sold, for an amount equivalent on a debt-free basis to $1,114 million. The result of this transaction was an after-tax gain of $394.3 million, calculated as the net proceeds of the sale less the book value of net assets held for sale, the corresponding tax effect and related expenses.

Analysis of the result of discontinued operations

(i) Income for discontinued operations

(all amounts in thousands of U.S. dollars)	Six-month period ended June 30,
	2009			2008
	(Unaudited)
Gross (loss) profit		(13,308	)		64,055
Operating (loss) income		(23,027	)		37,033
After tax gain on the sale of pressure control business		-			394,323
Result for discontinued operations		(28,138	)		416,906

(ii) Net cash flows attributable to discontinued operations

Cash flows provided by operating activities in 2009 amounted to $1.8 million. Cash flow used in investing activities amounted to $0.8. Cash flow provided by financing activities amounted to $5.3. These amounts were estimated only for disclosure purposes, as cash flows from these discontinued operations were not managed separately from other cash flows.

Cash and cash equivalents from discontinued operations increased by $6.3 million in 2009.

Cash flows provided by operating activities in 2008 amounted to $28.8 million. Cash flow used in investing activities amounted to $5.6 million. Cash flow provided by financing activities amounted to $4.8. These amounts were estimated only for disclosure purposes, as cash flows from these discontinued operations were not managed separately from other cash flows.

Cash and cash equivalents from discontinued operations increased by $28.0 million in 2008.

13           Related party transactions

Based on the information most recently available to the Company, as of  June 30, 2009:  

·   San Faustin N.V. owned 713,605,187 shares in the Company, representing 60.45% of the Company’s capital and voting rights.

·   San Faustín N.V. owned all of its shares in the Company through its wholly-owned subsidiary I.I.I. Industrial Investments Inc.

32

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

·   Rocca & Partners S.A. controlled a significant portion of the voting power of San Faustín N.V. and had the ability to influence matters affecting, or submitted to a vote of the shareholders of San Faustín N.V., such as the election of directors, the approval of certain corporate transactions and other matters concerning the company’s policies.

·   There were no controlling shareholders for Rocca & Partners S.A.

·   Tenaris’s directors and executive officers as a group owned 0.17% of the Company’s outstanding shares, while the remaining 39.38% were publicly traded.

At June 30, 2009, the closing price of Ternium S.A. (“Ternium”) ADS as quoted on the New York Stock Exchange was $17.26 per ADS, giving Tenaris’s ownership stake a market value of approximately $396.5 million. At June 30, 2009, the carrying value of Tenaris’s ownership stake in Ternium was approximately $553.4 million.

Transactions and balances disclosed as with “Associated” companies are those with companies over which Tenaris exerts significant influence or joint control in accordance with IFRS, but does not have control. All other transactions with related parties which are not Associated and which are not consolidated are disclosed as “Other”.

The following transactions were carried out with related parties:

(all amounts in thousands of U.S. dollars)		(Unaudited)
	Six month period ended June 30, 2009
		Associated (1)	Other	Total
(i)	Transactions (3)
	(a) Sales of goods and services
	Sales of goods	8,789	60,150	68,939
	Sales of services	7,134	2,795	9,929
		15,923	62,945	78,868
	(b) Purchases of goods and services
	Purchases of goods	20,611	6,313	26,924
	Purchases of services	48,670	32,849	81,519
		69,281	39,162	108,443

			(Unaudited)
	Six month period ended June 30, 2008
		Associated (2)	Other	Total
(i)	Transactions (4)
	(a) Sales of goods and services
	Sales of goods	32,893	17,365	50,258
	Sales of services	11,711	1,985	13,696
		44,604	19,350	63,954
	(b) Purchases of goods and services
	Purchases of goods	45,501	7,460	52,961
	Purchases of services	55,390	31,818	87,208
		100,891	39,278	140,169

33

Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

			(Unaudited)
	At June 30, 2009
		Associated (1)	Other	Total
(ii)	Period-end balances
	(a) Arising from sales / purchases of goods / services
	Receivables from related parties	20,607	14,674	35,281
	Payables to related parties	(28,282)	(5,354)	(33,636)
		(7,675)	9,320	1,645
	(b) Financial debt
	Borrowings	(1,621)	-	(1,621)

	At December 31, 2008
		Associated (1)	Other	Total
(ii)	Year-end balances
	(a) Arising from sales / purchases of goods / services
	Receivables from related parties	50,137	15,504	65,641
	Payables to related parties	(44,470)	(5,974)	(50,444)
		5,667	9,530	15,197
	(b) Financial debt
	Borrowings	(2,294)	-	(2,294)

(1) Includes Ternium S.A. and its subsidiaries (“Ternium”), Condusid C.A. (“Condusid”), Finma S.A.I.F (“Finma”), Lomond Holdings B.V.

group (“Lomond”), Socotherm Brasil S.A. (“Socotherm”) and Hydril Jindal International Private Ltd (“Hydril Jindal”).

(2) Includes Ternium, Condusid, Finma, Lomond, Socotherm, Hydril Jindal and TMK – Hydril JV.

(3) Includes $2.5 million of puchases of nationalized Venezuelan subsidiaries.

(4) Includes $12.9 million of sales and $6.6 million of puchases of nationalized Venezuelan subsidiaries.

14        Processes in Venezuela

(a) Investment in Ternium: Sidor nationalization process

On May 7, 2009, Ternium completed the transfer of its entire 59.7% interest in Sidor to CVG. The transfer was effected as a result of Venezuela’s Decree Law 6058, which ordered that Sidor and its subsidiaries and associated companies be transformed into state-owned enterprises and declared the activities of such companies of public and social interest. While CVG had assumed operational control of Sidor on July 12, 2008, Ternium had retained formal title over the shares until May 7, 2009. Ternium agreed to receive an aggregate amount of $1.97 billion as compensation for its Sidor shares. Of that amount, CVG paid $400 million in cash on May 7, 2009. The balance was divided in two tranches: the first tranche, of $945 million, will be paid in six equal quarterly installments, while the second tranche will be paid at maturity in November 2010, subject to quarterly mandatory prepayment events based on the increase of the WTI crude oil price over its May 6, 2009 level.

(b) Nationalization of Venezuelan Subsidiaries

Within the framework of Decree Law 6058, on May 22, 2009, Venezuela’s President Hugo Chávez announced the nationalization of, among other companies, the Company’s majority-owned subsidiaries TAVSA – Tubos de Acero de Venezuela S.A. (“Tavsa”) and, Matesi, Materiales Siderurgicos S.A (“Matesi”), and Complejo Siderurgico de Guayana, C.A (“Comsigua”), in which the Company has a minority interest (collectively, “the Venezuelan Companies”). On May 25, 2009, the Minister of Basic Industries and Mines of Venezuela (“MIBAM”) issued official communications N°230/09 and 231/09, appointing the MIBAM’s representatives to the transition committees charged with overseeing the nationalization processes of Tavsa and Matesi. On May 29, 2009, the Company sent response letters to the MIBAM acknowledging the Venezuelan government’s decision to nationalize Tavsa and Matesi, appointing its representatives to the transition committees, and reserving all of its rights under contracts, investment treaties and Venezuelan and international law and the right to submit any controversy between the Company or its subsidiaries and Venezuela relating to Tavsa and Matesi’s nationalization to international arbitration, including arbitration administered by ICSID.

On July 14, 2009, President Chávez issued Decree 6796, which orders the acquisition of the Venezuelan Companies and provides that Tavsa will be held by the Ministry of Energy and Oil, while Matesi and Comsigua will be held by MIBAM. Decree 6796 also requires the Venezuelan government to create certain committees at each of the Venezuelan Companies; each transition committee must ensure the nationalization of each Venezuelan Company and the continuity of its operations, and each technical committee (to be composed of representatives of Venezuela and the private sector) must negotiate over a 60-day period (extendable by mutual agreement) a fair price for each Venezuelan Company to be transferred to Venezuela. In the event the parties fail to reach agreement by the expiration of the 60-day period (or any extension thereof), the applicable Ministry will assume control and exclusive operation of the relevant Venezuelan Company, and the Executive Branch will order their expropriation in accordance with the Venezuelan Expropriation Law. The Decree also specifies that all facts and activities there under are subject to Venezuelan law and any disputes relating thereto must submitted to Venezuelan courts.

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Tenaris S.A - Half-year report 2009

Consolidated Condensed Interim Financial Statements for the six-month period ended June 30, 2009

The Company’s investments in Tavsa, Matesi and Comsigua are protected under applicable bilateral investment treaties, including the bilateral investment treaty between Venezuela and the Belgian-Luxembourgish Union, and, as noted above, Tenaris continues to reserve all of its rights under contracts, investment treaties and Venezuelan and international law, and to consent to the jurisdiction of the ICSID in connection with the nationalization process.

Based on the facts and circumstances described above and following the guidance set forth by IAS 27, the Company ceased consolidating the Venezuelan Companies results of operations and cash flows as from June 30, 2009 and classified its investments in the Venezuelan Companies as financial assets based on the definitions contained in paragraphs 11(c)(i) and 13 of IAS 32.

(b) Nationalization of Venezuelan Subsidiaries (Cont.)

The Company classified its interests in the Venezuelan Companies as available-for-sale investments since management believes they do not fulfill the requirements for classification within any of the remaining categories provided by IAS 39 and such classification is the most appropriate accounting treatment applicable to non-voluntary dispositions of assets.

In addition to the disclosed amounts, Tenaris subsidiaries have also net receivables with the Venezuelan Companies as of June 30, 2009 for a total amount of $25.4 million.

The Company records its interest in the Venezuelan Companies at its carrying amount at June 30, 2009, and not at fair value, following the guidance set forth by paragraphs 46(c), AG80 and AG81 of IAS 39.

 /s/ Ricardo Soler

Ricardo Soler

Chief Financial Officer

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Corporate Information

Registered Office

46A, avenue John F. Kennedy

L-1855 Luxembourg

(352) 26 47 89 78 tel

(352) 26 47 89 79 fax

Principal Offices
Av. L. N. Alem 1067 27th Floor	2200 West Loop South, Suite 800
(C1001AAF) Buenos Aires, Argentina	Houston, TX 77027, USA
(54) 11 4018 4100 tel	(1) 713 767 4400 tel
(54) 11 4018 1000 fax	(1) 713 767 4444 fax
Piazza Caduti 6 Luglio 1944, 1	Edificio Parque Reforma
24044 Dalmine (Bergamo), Italy	Campos Elíseos 400 17th Floor
(39) 035 560 1111 tel	11560 Mexico, D.F.
(39) 035 560 3827 fax	(52) 55 5282 9900 tel
	(52) 55 5282 9961 fax

INVESTOR INFORMATION

Investor Relations Director

Giovanni Sardagna

Phones	General Inquiries
USA 1 888 300 5432	investors@tenaris.com
Argentina (54) 11 4018 2928
Italy (39) 02 4384 7654
Mexico (52) 55 5282 9929

Stock Information	ADS Depositary Bank
New York Stock Exchange (TS)	The Bank of New York
Mercato Telematico Azionario (TEN)	CUSIP No. 88031M019
Mercado de Valores de Buenos Aires (TS)
Bolsa Mexicana de Valores, S.A. de C.V. (TS)

Internet

www.tenaris.com

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