Exhibit 99.1

W. R. Berkley Corporation	NEWS RELEASE
475 Steamboat Road
Greenwich, Connecticut 06830
(203) 629-3000

FOR IMMEDIATE RELEASE	CONTACT:	Karen A. Horvath
		Vice President — External
		Financial Communications
		(203) 629-3000

W. R. BERKLEY CORPORATION REPORTS SECOND QUARTER RESULTS
Net Income up 13.2% to $110 Million

     Greenwich, CT, July 26, 2010 — W. R. Berkley Corporation (NYSE: WRB) today reported net income for the second quarter of 2010 of $110 million, or 70 cents per share, compared with $97 million, or 59 cents per share, for the second quarter of 2009. Operating income for the second quarter of 2010 was $102 million, or 65 cents per share, compared with $100 million, or 60 cents per share, for the corresponding quarter of 2009. Operating income is a non-GAAP financial measure defined by the Company as net income excluding income and losses from investment funds and net investment gains and losses.

Summary Financial Data
(Amounts in thousands, except per share data)

	Second Quarter				Six Months
	2010		2009		2010		2009
Gross premiums written	$	1,113,469	$	1,054,577	$	2,239,589	$	2,202,819
Net premiums written		961,354		908,912		1,945,304		1,932,384
Net income		110,207		97,387		228,817		77,041
Net income per diluted share		0.70		0.59		1.44		0.46
Operating income		101,775		99,930		213,475		217,226
Operating income per diluted share		0.65		0.60		1.35		1.30

W. R. Berkley Corporation Page 2

Second quarter highlights included:

• Net premiums written increased 6%.

• GAAP combined ratio was 94.4%.

• Return on equity was 12.3%.

• Book value per share increased 4% to $24.81.

• Repurchased 5.1 million shares of common stock at an average cost of $26.87 per share and an aggregate cost of $136 million.

     Commenting on the Company’s performance, William R. Berkley, chairman and chief executive officer, said: “We are pleased with our second quarter results. Our new enterprises continue to gain traction, and their growth led to an increase in overall premiums for the first time in fifteen quarters. Written premium grew by more than 5.5% in the quarter as the growth in these new businesses more than offset the slight decline in our established business units. Our calendar year combined ratio was under ninety-five, and we continue to book our current accident year in a prudent manner. We are particularly cognizant of assuring adequate pricing for our new business units. There are a growing number of signs of a coming turn in the cycle, as prices are beginning to stabilize in most areas. Overall, prices were down less than one percent for the quarter. Given the current investment environment, adequate industry returns can only be achieved by improved underwriting results.

     “The investment portfolio changed only slightly during the quarter. The current shape of the yield curve and the absolute level of returns available for long term securities caused us to reconsider our plans for extending the portfolio duration, which remained at 3.6 years. We continued to modestly shift our municipal portfolio away from general obligation bonds to other types of municipal securities.

     “Looking ahead, we remain cautiously optimistic. With current available yields down over 200 basis points from historic industry investment returns, investment results cannot be the drivers of profitability for property casualty companies. We believe that current investment yields and unsatisfactory underwriting year pricing are generating inadequate current levels of return for the industry. As we approach the end of the year, it is likely our competitors will reach a similar conclusion, and pricing will improve,” Mr. Berkley concluded.

W. R. Berkley Corporation	Page 3
Webcast Conference Call

          The Company will hold its quarterly conference call with analysts and investors to discuss its earnings and other information on Tuesday, July 27, 2010 at 9:00 a.m. eastern time. The conference call will be webcast live on the Company’s website at www.wrberkley.com. A recording of the call will be available on the Company’s website approximately two hours after the end of the conference call.

About W. R. Berkley Corporation

          Founded in 1967, W. R. Berkley Corporation is an insurance holding company that is among the largest commercial lines writers in the United States and operates in five segments of the property casualty insurance business: specialty insurance, regional property casualty insurance, alternative markets, reinsurance and international.

Forward Looking Information

This is a “Safe Harbor” Statement under the Private Securities Litigation Reform Act of 1995. Any forward-looking statements contained herein, including statements related to our outlook for the industry and for our performance for the year 2010 and beyond, are based upon the Company’s historical performance and on current plans, estimates and expectations. The inclusion of this forward-looking information should not be regarded as a representation by us or any other person that the future plans, estimates or expectations contemplated by us will be achieved. They are subject to various risks and uncertainties, including but not limited to: the cyclical nature of the property casualty industry; the long-tail and potentially volatile nature of the insurance and reinsurance business; product demand and pricing; claims development and the process of estimating reserves; investment risks, including those of our portfolio of fixed maturity securities and investments in equity securities, including investments in financial institutions, municipal bonds, mortgage-backed securities, loans receivable, investment funds, merger arbitrage and private equity investments; the impact of significant competition; the potential impact of the economic downturn, and any legislative, regulatory, accounting or other initiatives taken in response to it, on our results and financial condition; the uncertain nature of damage theories and loss amounts; natural and man-made catastrophic losses, including as a result of terrorist activities; the success of our new ventures or acquisitions and the availability of other opportunities; the availability of reinsurance; our retention under the Terrorism Risk Insurance Programs Reauthorization Act of 2007; the ability of our reinsurers to pay reinsurance recoverables owed to us; foreign currency and political risks relating to our international operations; other legislative and regulatory developments, including those related to business practices in the insurance industry; changes in the ratings assigned to us or our insurance company subsidiaries by rating agencies; the availability of dividends from our insurance company subsidiaries; our ability to attract and retain qualified employees; and other risks detailed from time to time in the Company’s filings with the Securities and Exchange Commission. These risks and uncertainties could cause our actual results for the year 2010 and beyond to differ materially from those expressed in any forward-looking statement we make. Any projections of growth in our net premiums written and management fees would not necessarily result in commensurate levels of underwriting and operating profits. Forward-looking statements speak only as of the date on which they are made, and the Company undertakes no obligation to update publicly or revise any forward-looking statement, whether as a result of new information, future developments or otherwise.

# # #

W. R. Berkley Corporation Page 4

Consolidated Financial Summary
(Amounts in thousands, except per share data)

	Second Quarter						Six Months
	2010			2009			2010			2009
Revenues:
Net premiums written	$	961,354		$	908,912		$	1,945,304		$	1,932,384
Change in unearned premiums		(13,226	)		42,260			(66,615	)		(2,004	)
Net premiums earned		948,128			951,172			1,878,689			1,930,380
Net investment income		128,191			132,135			267,034			270,351
Income (losses) from investment funds		1,540			(37,821	)		6,258			(152,895	)
Insurance service fees		20,390			25,257			41,875			51,840
Net investment gains (losses):
Net realized gains on investment sales		11,534			49,224			20,028			62,616
Other-than-temporary impairments		—			(23,932	)		(2,582	)		(134,132	)
Less other-than-temporary impairments recognized in other comprehensive income		—			8,604			—			8,604
Net investment gains (losses)		11,534			33,896			17,446			(62,912	)
Revenues from wholly-owned investees		52,929			49,942			104,505			80,845
Other income		356			517			808			1,110
Total revenues		1,163,068			1,155,098			2,316,615			2,118,719
Expenses:
Losses and loss expenses		570,475			597,267			1,120,448			1,207,712
Other operating costs and expenses		370,823			365,514			738,790			722,861
Expenses from wholly-owned investees		49,934			46,791			98,908			76,745
Interest expense		26,014			20,213			52,055			40,437
Total expenses		1,017,246			1,029,785			2,010,201			2,047,755
Income before income taxes		145,822			125,313			306,414			70,964
Income tax (expense) benefit		(35,598	)		(27,881	)		(77,409	)		6,184
Net income before noncontrolling interests		110,224			97,432			229,005			77,148
Noncontrolling interests		(17	)		(45	)		(188	)		(107	)
Net income to common stockholders	$	110,207		$	97,387		$	228,817		$	77,041
Net income per share:
Basic	$	0.73		$	0.61		$	1.50		$	0.48
Diluted	$	0.70		$	0.59		$	1.44		$	0.46
Average shares outstanding:
Basic		151,215			160,008			152,324			160,546
Diluted		157,461			166,226			158,539			166,716

W. R. Berkley Corporation Page 5

Operating Results by Segment
(Amounts in thousands, except ratios (1))

	Second Quarter						Six Months
	2010			2009			2010			2009
Specialty: (2)
Gross premiums written	$	404,407		$	394,889		$	747,339		$	759,783
Net premiums written		342,275			338,683			644,203			661,240
Premiums earned		316,513			346,052			629,466			703,980
Pre-tax income		75,177			65,920			150,847			93,664
Loss ratio		57.2	%		60.0	%		57.6	%		61.4	%
Expense ratio		32.7	%		29.8	%		33.2	%		30.3	%
GAAP combined ratio		89.9	%		89.8	%		90.8	%		91.7	%
Regional:(2)
Gross premiums written	$	286,711		$	317,445		$	589,352		$	640,246
Net premiums written		258,543			277,730			530,575			559,765
Premiums earned		266,629			281,903			530,298			567,519
Pre-tax income		25,505			11,677			67,469			30,042
Loss ratio		62.2	%		66.6	%		59.7	%		63.8	%
Expense ratio		35.5	%		34.2	%		35.5	%		33.6	%
GAAP combined ratio		97.7	%		100.8	%		95.2	%		97.4	%
Alternative Markets:
Gross premiums written	$	146,599		$	113,960		$	387,950		$	362,834
Net premiums written		117,092			99,486			327,497			325,201
Premiums earned		155,227			151,309			310,012			303,302
Pre-tax income		45,571			36,961			96,556			67,395
Loss ratio		65.2	%		66.4	%		64.9	%		64.3	%
Expense ratio		26.0	%		25.7	%		25.8	%		24.9	%
GAAP combined ratio		91.2	%		92.1	%		90.7	%		89.2	%
Reinsurance:(2)
Gross premiums written	$	114,646		$	116,217		$	221,015		$	224,073
Net premiums written		107,633			107,055			206,404			207,888
Premiums earned		105,632			94,257			205,190			199,880
Pre-tax income		30,157			21,228			64,577			24,227
Loss ratio		55.7	%		56.4	%		53.1	%		60.1	%
Expense ratio		41.0	%		42.9	%		42.4	%		39.1	%
GAAP combined ratio		96.7	%		99.3	%		95.5	%		99.2	%
International:(2)
Gross premiums written	$	161,106		$	112,066		$	293,933		$	215,883
Net premiums written		135,811			85,958			236,625			178,290
Premiums earned		104,127			77,651			203,723			155,699
Pre-tax income		6,586			720			6,959			6,888
Loss ratio		61.1	%		61.9	%		64.4	%		63.0	%
Expense ratio		41.2	%		38.8	%		42.4	%		38.2	%
GAAP combined ratio		102.3	%		100.7	%		106.8	%		101.2	%

W. R. Berkley Corporation Page 6

Operating Results by Segment (Continued)
(Amounts in thousands, except ratios (1))

	Second Quarter						Six Months
	2010			2009			2010			2009
Corporate and Eliminations:
Net investment gains (losses)	$	11,534		$	33,896		$	17,446		$	(62,912	)
Interest expense		(26,014	)		(20,213	)		(52,055	)		(40,437	)
Other revenues and expenses (3)		(22,694	)		(24,876	)		(45,385	)		(47,903	)
Pre-tax loss		(37,174	)		(11,193	)		(79,994	)		(151,252	)
Consolidated:
Gross premiums written	$	1,113,469		$	1,054,577		$	2,239,589		$	2,202,819
Net premiums written		961,354			908,912			1,945,304			1,932,384
Premiums earned		948,128			951,172			1,878,689			1,930,380
Pre-tax income		145,822			125,313			306,414			70,964
Loss ratio		60.2	%		62.8	%		59.6	%		62.6	%
Expense ratio		34.2	%		32.5	%		34.6	%		32.0	%
GAAP combined ratio		94.4	%		95.3	%		94.2	%		94.6	%

(1)	Loss ratio is losses and loss expenses incurred expressed as a percentage of premiums earned. Expense ratio is underwriting expenses expressed as a percentage of premiums earned. Underwriting expenses do not include expenses related to insurance services or unallocated corporate expenses. GAAP combined ratio is the sum of the loss ratio and the expense ratio.
(2)	For the second quarters of 2010 and 2009, catastrophe and weather-related losses were $30 million and $28 million, respectively. For the first six months of 2010 and 2009, catastrophe and weather-related losses were $53 million and $36 million, respectively.
(3)	Other revenues and expenses include corporate investment income, expenses not allocated to the business segments and revenues and expenses from investments in wholly-owned, non-insurance subsidiaries that are consolidated for financial reporting purposes.

W. R. Berkley Corporation Page 7

Selected Balance Sheet Information
(Amounts in thousands, except per share data)

	June 30,		December 31,
	2010		2009
Net invested assets (1)	$	13,711,656	$	13,726,213
Total assets		17,416,926		17,328,596
Reserves for losses and loss expenses		9,109,638		9,071,671
Senior notes and other debt		1,342,601		1,345,481
Junior subordinated debentures		242,682		249,793
Common stockholders’ equity (2) (3)		3,682,362		3,596,067
Common stock outstanding (3)		148,421		156,552
Common stockholders’ equity per share (3)		24.81		22.97

(1)	Net invested assets include investments, cash investments and cash equivalents, trading accounts receivable from brokers and clearing organizations, trading account securities sold but not yet purchased and unsettled purchases.
(2)	After-tax unrealized investment gains were $329 million and $219 million as of June 30, 2010 and December 31, 2009, respectively. Unrealized currency translation losses were $58 million and $40 million as of June 30, 2010 and December 31, 2009, respectively.
(3)	During the first six months of 2010, the Company repurchased 8.9 million shares of its common stock at an average cost of $25.97 per share and an aggregate cost of $231 million.

W. R. Berkley Corporation Page 8

Supplemental Information
(Amounts in thousands)

	Second Quarter						Six Months
	2010			2009			2010			2009
Reconciliation of operating income to net income:
Operating income (1)	$	101,775		$	99,930		$	213,475		$	217,226
Investment gains (losses), net of tax		7,449			22,041			11,292			(40,803	)
Income (losses) from investment funds, net of tax		983			(24,584	)		4,050			(99,382	)
Net income	$	110,207		$	97,387		$	228,817		$	77,041
Return on equity:
Net income (2)		12.3	%		12.8	%		12.7	%		5.1	%
Operating income (1) (2)		11.3	%		13.1	%		11.9	%		14.3	%
Cash flow:
Cash flow from operations before cash transfers to/from trading account (3)	$	129,511		$	189,208		$	186,670		$	280,768
Cash transfers to/from trading account		—			(220,000	)		—			(290,000	)
Cash flow from (used in) operations	$	129,511		$	(30,792	)	$	186,670		$	(9,232	)
Other operating costs and expenses:
Underwriting expenses	$	324,599		$	308,970		$	650,202		$	616,926
Service expenses		18,411			20,503			36,955			42,560
Net foreign currency losses (gains)		1,316			5,427			(3,711	)		5,959
Other costs and expenses		26,497			30,614			55,344			57,416
Total	$	370,823		$	365,514		$	738,790		$	722,861

(1)	Operating income is a non-GAAP financial measure defined by the Company as net income excluding income and losses from investment funds and net investment gains and losses. Management believes that excluding income and losses from investment funds and net investment gains and losses, which result primarily from changes in general economic conditions, provides a useful indicator of trends in the Company’s underlying operations.
(2)	Return on equity represents net income and net operating income expressed on an annualized basis as a percentage of beginning of year stockholders’ equity.
(3)	Cash flow from operations before cash transfers to/from trading account is a non-GAAP financial measure that excludes cash contributions to and withdrawals from the arbitrage trading account. Management believes that cash transfers to and withdrawals from the arbitrage trading account are the result of changes in investment allocations and that excluding such transfers provides a useful measure of the Company’s cash flow.

W. R. Berkley Corporation Page 9

Investment Portfolio
June 30, 2010

			Carrying		Percent
	Cost		Value		of Total
Fixed maturity securities:
United States government and government agencies	$	1,519,879	$	1,586,226		11.6	%
State and municipal		5,451,318		5,694,685		41.5	%
Mortgage-backed securities
Agency		1,027,851		1,078,235		7.9	%
Residential — Prime		282,954		277,443		2.0	%
Residential — Alt A		68,218		65,819		0.5	%
Commercial		44,876		37,327		0.3	%
Total mortgage-backed securities		1,423,899		1,458,824		10.7	%
Corporate
Industrial		820,182		886,960		6.5	%
Financial		544,061		552,700		4.0	%
Utilities		183,998		195,928		1.4	%
Asset-backed		226,186		209,633		1.5	%
Other		125,109		125,896		1.0	%
Total corporate		1,899,536		1,971,117		14.4	%
Foreign government and foreign government agencies		423,381		436,900		3.2	%
Total fixed maturity securities		10,718,013		11,147,752		81.4	%
Equity securities available for sale:
Preferred stocks
Financial		110,102		93,994		0.7	%
Real Estate		69,743		69,822		0.5	%
Utilities		52,894		51,936		0.4	%
Common stock		48,120		141,477		1.0	%
Total equity securities available for sale		280,859		357,229		2.6	%
Arbitrage trading account		498,368		498,368		3.6	%
Investment in arbitrage funds		58,564		58,564		0.4	%
Investment funds		422,255		421,394		3.1	%
Loans receivable		373,605		373,605		2.7	%
Cash and cash equivalents (1)		854,744		854,744		6.2	%
Net invested assets	$	13,206,408	$	13,711,656		100.0	%

(1) Includes trading accounts receivable from brokers and clearing organizations, trading account securities sold but not yet purchased and unsettled purchases.

W. R. Berkley Corporation Page 10

State and Municipal Bonds (1)
June 30, 2010

															% of
	CA		NY		IL		NJ		FL		NV		Total		Total
Pre-refunded (2)	$	278,065	$	66,565	$	88,433	$	96,381	$	5,934	$	10,937	$	546,315		9.6	%
Corporate-backed		51,414		8,799		—		—		5,012		—		65,225		1.2	%
Special revenue (3)		172,157		287,970		140,932		85,734		45,731		3,235		735,759		12.9	%
Non-state general obligation (4)		76,686		21,260		35,957		—		7,130		6,480		147,513		2.6	%
State general obligation		10,521		61,379		26,023		68,240		—		—		166,163		2.9	%
Total	$	588,843	$	445,973	$	291,345	$	250,355	$	63,807	$	20,652		1,660,975		29.2	%
All other states														4,033,710		70.8	%
Total state and municipal bonds													$	5,694,685		100.0	%

(1)	Overall average rating is AA.
(2)	Bonds that have been pre-refunded with United States government securities.
(3)	Bonds supported by a specific revenue pledge.
(4)	Bonds issued by municipalities, counties and other local governments.