UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

Investment Company Act File Number: 811-05833

T. Rowe Price Institutional International Funds, Inc.

(Exact name of registrant as specified in charter)

100 East Pratt Street, Baltimore, MD 21202

(Address of principal executive offices)

David Oestreicher

100 East Pratt Street, Baltimore, MD 21202

(Name and address of agent for service)

Registrant’s telephone number, including area code: (410) 345-2000

Date of fiscal year end: December 31

Date of reporting period: June 30, 2015

The views and opinions in this report were current as of June 30, 2015. They are not guarantees of performance or investment results and should not be taken as investment advice. Investment decisions reflect a variety of factors, and the managers reserve the right to change their views about individual stocks, sectors, and the markets at any time. As a result, the views expressed should not be relied upon as a forecast of the fund’s future investment intent. The report is certified under the Sarbanes-Oxley Act, which requires mutual funds and other public companies to affirm that, to the best of their knowledge, the information in their financial reports is fairly and accurately stated in all material respects.

Developed market international bonds lost ground in U.S. dollar terms as yields increased and the U.S. dollar strengthened against many other currencies. Volatility in global fixed income and currency markets increased during the six-month reporting period as the Federal Reserve prepared to raise interest rates while the European Central Bank (ECB) and the Bank of Japan (BoJ) maintained or expanded their accommodative monetary policies. Emerging markets sovereign debt also declined, although corporate bonds from issuers in developing countries generated positive returns that were among the strongest in the broad fixed income asset class.

The Institutional International Bond Fund returned -3.99% for the six-month period ended June 30, 2015. The fund outperformed the benchmark Barclays Global Aggregate ex USD Bond Index. Country allocation, currency positioning, and sector selection all contributed to the fund’s outperformance of the benchmark.

Co-portfolio Manager Christopher Rothery has announced that he will retire at the end of 2015 after more than 20 years with T. Rowe Price. Effective December 31, 2015, Kenneth Orchard will replace Mr. Rothery and join Arif Husain as the fund’s co-portfolio manager and cochairman of the fund’s Investment Advisory Committee. After earning a B.A. in international relations from the University of British Columbia and an M.Sc. in public financial policy from the London School of Economics, Mr. Orchard worked as both an economist and an assistant portfolio manager before joining T. Rowe Price International’s Fixed Income Division in 2010. Mr. Orchard has worked closely with the fund’s management team, specializing in European countries, and served as a member of the fund’s Investment Advisory Committee since 2012.

In March, the Federal Reserve removed the word “patient” from its policy meeting statement regarding the timing of its first interest rate increase, paving the way for it to eventually raise rates. This could happen as early as this fall, though the timing remains uncertain. In contrast to the Fed, the ECB and the BoJ are maintaining stimulative policies. In January, the ECB announced that it would launch a large-scale quantitative easing (QE) program involving purchases of eurozone sovereign debt. The ECB began buying €60 billion of bonds per month beginning in March and said it would continue the purchases through at least September 2016. The sovereign QE program supported a tentative recovery in the eurozone. Despite the BoJ’s ongoing aggressive QE program and targeted structural reforms, Japan’s domestic consumption has remained stagnant. The Bank of England has held its benchmark lending rate at 0.5% since March 2009. The UK central bank’s policy cycle is expected to be more in sync with the Fed than the ECB and BoJ, but likely with a lag.

Intermediate- and longer-term U.S. Treasury yields increased over the course of the six-month period. The yield on the 10-year U.S. Treasury note rose to 2.35% at the end of June from 2.17% six months prior. The German 10-year sovereign note’s yield decreased to a record low of 0.05%, while most shorter-maturity German debt traded at negative yields amid fears of deflation in the eurozone. Yields bottomed in April and began a rapid ascent amid signs of stronger European growth, and the reporting period ended with a period of elevated interest rate volatility. Periphery eurozone debt traded in a similar pattern, though with higher yields given its lower credit quality. As the reporting period ended, Greece’s negotiations over payments due to the International Monetary Fund and the ECB were a heightened risk factor for the eurozone and markets in general. Emerging markets sovereign debt denominated in U.S. dollars generated a slight overall gain, while locally denominated bonds from developing countries dropped sharply in dollar terms as the greenback strengthened.

European investment-grade corporate debt fell in local currency terms. However, high yield corporate bonds denominated in euros produced solid returns. Emerging markets corporates, which are primarily denominated in U.S. dollars, were one of the strongest-performing sectors in the broad fixed income asset class for the six-month reporting period.

The strength of the U.S. dollar, driven by expectations for the Fed to increase rates while many other global central banks cut them, dominated the currency market. The euro lost nearly 8% against the dollar for the six-month period, although toward the end of the period it gained back some of the ground it lost earlier in 2015. The yen’s decline against the greenback was more modest. Emerging markets currencies in general were volatile and declined against the U.S. dollar, with higher volatility experienced primarily by countries that are major oil producers or, conversely, oil importers. For example, the Mexican peso declined more than 6% against the dollar, apparently driven by generalized risk aversion resulting from the oil decline.

The fund’s country allocation and exposure to interest rate changes was a positive relative performance factor. Our shorter-than-benchmark duration in eurozone sovereign bonds helped dampen the negative price effects of the sharp rise in yields on core and periphery eurozone government debt in April and May. We added to eurozone duration in May after the heavy sell-off. Similar conservative duration positioning in Japan and the UK also benefited relative performance. Following the Conservative Party victory in May’s UK general elections, we extended the duration of our UK holdings. On the negative side, the portfolio’s short relative duration in Canada detracted from relative returns in January when Canadian government bond yields fell sharply after the country’s central bank made a surprise interest rate cut to stimulate an economy hurt by lower oil prices.

Sector selection also made a positive contribution to relative performance in the six-month period. The portfolio’s allocations to high yield bonds denominated in euros and to Japanese inflation-linked bonds both benefited relative returns as those segments held up better than the broad non-U.S. fixed income market. In addition to the European high yield exposure, we maintained a benchmark-neutral allocation to investment-grade corporate bonds in Europe.

We trimmed the portfolio’s exposure to emerging markets debt—both sovereign and corporate bonds—because the asset class could experience selling pressure as the Fed moves closer to raising U.S. rates. While emerging markets bonds remain attractive from a long-term, fundamental point of view, we weigh this against their liquidity limitations when analyzing their value relative to developed markets debt. Within the emerging markets allocation, we maintained an overweight to Mexico, which we expect to benefit from structural reforms as well as its close economic ties to the U.S. We increased the portfolio’s allocations to Poland and Malaysia and maintained out-of-benchmark exposure to China and Romania.

The fund’s currency positioning also contributed to its relative performance. In developed market currencies, we were underweight the euro, which particularly helped relative returns in January after the ECB announced the aggressive expansion of its QE program into government debt. Although we added euro exposure over the course of the six-month period, it is still one of the most significant currency underweights because we expect further euro weakness as the ECB’s asset purchases continue. Toward the end of the reporting period, we added to our Japanese yen exposure as we believe that further yen depreciation will be limited after its extended decline against the U.S. dollar.

In emerging markets currencies, we slightly reduced our overweight in the Mexican peso. We maintained the portfolio’s exposure to the Indian rupee and the Chinese renminbi, neither of which is in the benchmark. The portfolio’s overweight to the Polish zloty versus the euro benefited relative performance, while an underweight to the Israeli shekel against the U.S. dollar detracted.

There is a considerable amount of uncertainty in the current market environment, and we expect that to continue as monetary policies diverge globally. The Fed and the Bank of England are preparing to raise rates, while the ECB and BoJ maintain their expansive QE programs. The situation in Greece seems to have moved to the back burner for the time being, but the agreement between the country and its lenders to free up more bailout funding has only delayed a resolution to how Greece will deal with its crippling debt levels. In addition, it remains to be seen how effectively the Chinese government will respond to its slowing economic growth.

However, the most significant risk facing the financial markets is that the Fed’s move to normalize monetary policy by raising rates after six years with the federal funds rate at essentially 0% will trigger a systemic reduction in liquidity. The markets seem to be focusing on the timing of the first rate hike, but the path of subsequent increases and the ending level of benchmark rates are more important. If an inflation surprise prompts the Fed to tighten more rapidly than the U.S. Treasury market is currently expecting, volatility and yields could suddenly increase.

With this threat looming, volatility in the markets will probably remain elevated. On the positive side, this will likely produce opportunities for relative value trading between markets at different points in their interest rate cycles. In this environment, we believe that the extended reach of T. Rowe Price’s global sovereign, credit, and equity research platforms, combined with our emphasis on collaboration across those platforms, gives us a critical edge in analyzing both risks and opportunities in both developed and emerging fixed income markets.

Arif Husain
President of the International Fixed Income Division, co-portfolio manager, and cochairman of the fund’s Investment Advisory Committee

Christopher J. Rothery
Co-portfolio manager and cochairman of the fund’s Investment Advisory Committee

The committee chairmen have day-to-day responsibility for the portfolio and work with committee members in developing and executing the fund’s investment program.

In section 1, the portfolio manager table under “Management” with respect to the Institutional International Bond Fund is supplemented as follows:

Effective December 31, 2015, Christopher J. Rothery will retire from T. Rowe Price International and step down from his responsibilities as the fund’s co-portfolio manager and Co-chairman of the fund’s Investment Advisory Committee. Effective December 31, 2015, Kenneth Orchard will replace Mr. Rothery and join Arif Husain as the fund’s co-portfolio manager and Co-chairman of the fund’s Investment Advisory Committee. Mr. Orchard joined T. Rowe Price International in 2010.

In section 3, the disclosure under “Portfolio Management” with respect to the Institutional International Bond Fund is supplemented as follows:

Effective December 31, 2015, Kenneth Orchard will replace Christopher J. Rothery as Co-chairman of the fund’s Investment Advisory Committee. Mr. Orchard joined the Firm in 2010 and his experience dates from 2004. Since joining the Firm, he has served as a portfolio manager and credit research analyst. Prior to joining the Firm, he worked as a senior credit officer at Moody’s Investors Service.

Funds that invest overseas generally carry more risk than funds that invest strictly in U.S. assets, including unpredictable changes in currency values. Investments in emerging markets are subject to abrupt and severe price declines and should be regarded as speculative. The economic and political structures of developing nations, in most cases, do not compare favorably with the U.S. or other developed countries in terms of wealth and stability, and their financial markets often lack liquidity. Some countries also have legacies of hyperinflation, currency devaluations, and governmental interference in markets.

International investments are subject to currency risk, a decline in the value of a foreign currency versus the U.S. dollar, which reduces the dollar value of securities denominated in that currency. The overall impact on a fund’s holdings can be significant and long-lasting depending on the currencies represented in the portfolio, how each one appreciates or depreciates in relation to the U.S. dollar, and whether currency positions are hedged. Further, exchange rate movements are unpredictable, and it is not possible to effectively hedge the currency risks of many developing countries.

Bonds are also subject to interest rate risk, the decline in bond prices that usually accompanies a rise in interest rates, and credit risk, the chance that any fund holding could have its credit rating downgraded or that a bond issuer will default (fail to make timely payments of interest or principal), potentially reducing the fund’s income level and share price.

Barclays Global Aggregate ex USD Bond Index: An unmanaged index that tracks an international basket of bonds that contains government, corporate, agency, and mortgage-related bonds.

Credit spread: Measures the additional yield that investors demand as compensation for holding a bond with credit risk versus a similar-maturity Treasury security or other type of low-risk bond.

Duration: A measure of a bond’s or bond fund’s sensitivity to changes in interest rates. For example, a fund with a duration of six years would fall about 6% in response to a one-percentage-point rise in rates, and vice versa.

J.P. Morgan Emerging Markets Bond Index Global: Tracks U.S. dollar government bonds of 31 foreign countries.

Quasi-sovereign debt: Debt issued by a corporation and backed by the respective government, typically offering the higher yields of corporate debt with the added benefit of government support.

Weighted average maturity: A measure of a fund’s sensitivity to interest rates. In general, the longer the average maturity, the greater the fund’s sensitivity to interest rate changes. The weighted average maturity may take into account the interest rate readjustment dates for certain securities. Money funds must maintain a weighted average maturity of less than 60 days.

Performance and Expenses
T. Rowe Price Institutional International Bond Fund

This chart shows the value of a hypothetical $1 million investment in the fund over the past 10 fiscal year periods or since inception (for funds lacking 10-year records). The result is compared with benchmarks, which may include a broad-based market index and a peer group average or index. Market indexes do not include expenses, which are deducted from fund returns as well as mutual fund averages and indexes.

As a mutual fund shareholder, you may incur two types of costs: (1) transaction costs, such as redemption fees or sales loads, and (2) ongoing costs, including management fees, distribution and service (12b-1) fees, and other fund expenses. The following example is intended to help you understand your ongoing costs (in dollars) of investing in the fund and to compare these costs with the ongoing costs of investing in other mutual funds. The example is based on an investment of $1,000 invested at the beginning of the most recent six-month period and held for the entire period.

Actual Expenses
The first line of the following table (Actual) provides information about actual account values and actual expenses. You may use the information on this line, together with your account balance, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number on the first line under the heading “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes
The information on the second line of the table (Hypothetical) is based on hypothetical account values and expenses derived from the fund’s actual expense ratio and an assumed 5% per year rate of return before expenses (not the fund’s actual return). You may compare the ongoing costs of investing in the fund with other funds by contrasting this 5% hypothetical example and the 5% hypothetical examples that appear in the shareholder reports of the other funds. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period.

You should also be aware that the expenses shown in the table highlight only your ongoing costs and do not reflect any transaction costs, such as redemption fees or sales loads. Therefore, the second line of the table is useful in comparing ongoing costs only and will not help you determine the relative total costs of owning different funds. To the extent a fund charges transaction costs, however, the total cost of owning that fund is higher.

Financial Highlights
T. Rowe Price Institutional International Bond Fund
(Unaudited)

Portfolio of Investments^‡T. Rowe Price Institutional International Bond Fund
June 30, 2015 (Unaudited)

Statement of Assets and Liabilities
T. Rowe Price Institutional International Bond Fund
June 30, 2015 (Unaudited)
($000s, except shares and per share amounts)

Statement of Operations
T. Rowe Price Institutional International Bond Fund
(Unaudited)
($000s)

Statement of Changes in Net Assets
T. Rowe Price Institutional International Bond Fund
(Unaudited)
($000s)

Notes to Financial Statements
T. Rowe Price Institutional International Bond Fund
June 30, 2015 (Unaudited)

T. Rowe Price Institutional International Funds, Inc. (the corporation), is registered under the Investment Company Act of 1940 (the 1940 Act). The Institutional International Bond Fund (the fund) is a nondiversified, open-end management investment company established by the corporation. The fund commenced operations on May 31, 2007. The fund seeks to provide high current income and capital appreciation.

Basis of Preparation The fund is an investment company and follows accounting and reporting guidance in the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946 (ASC 946). The accompanying financial statements were prepared in accordance with accounting principles generally accepted in the United States of America (GAAP), including but not limited to ASC 946. GAAP requires the use of estimates made by management. Management believes that estimates and valuations are appropriate; however, actual results may differ from those estimates, and the valuations reflected in the accompanying financial statements may differ from the value ultimately realized upon sale or maturity.

Investment Transactions, Investment Income, and Distributions Income and expenses are recorded on the accrual basis. Premiums and discounts on debt securities are amortized for financial reporting purposes. Paydown gains and losses are recorded as an adjustment to interest income. Inflation adjustments to the principal amount of inflation-indexed bonds are reflected as interest income. Dividends received from mutual fund investments are reflected as dividend income; capital gain distributions are reflected as realized gain/loss. Dividend income and capital gain distributions are recorded on the ex-dividend date. Income tax-related interest and penalties, if incurred, would be recorded as income tax expense. Investment transactions are accounted for on the trade date. Realized gains and losses are reported on the identified cost basis. Distributions to shareholders are recorded on the ex-dividend date. Income distributions are declared daily and paid monthly. Capital gain distributions, if any, are generally declared and paid by the fund annually.

Currency Translation Assets, including investments, and liabilities denominated in foreign currencies are translated into U.S. dollar values each day at the prevailing exchange rate, using the mean of the bid and asked prices of such currencies against U.S. dollars as quoted by a major bank. Purchases and sales of securities, income, and expenses are translated into U.S. dollars at the prevailing exchange rate on the date of the transaction. The effect of changes in foreign currency exchange rates on realized and unrealized security gains and losses is reflected as a component of security gains and losses.

Redemption Fees A 2% fee is assessed on redemptions of fund shares held for 90 days or less to deter short-term trading and to protect the interests of long-term shareholders. Redemption fees are withheld from proceeds that shareholders receive from the sale or exchange of fund shares. The fees are paid to the fund and are recorded as an increase to paid-in capital. The fees may cause the redemption price per share to differ from the net asset value per share.

New Accounting Guidance In June 2014, FASB issued Accounting Standards Update (ASU) No. 2014-11, Transfers and Servicing (Topic 860), Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures. The ASU changes the accounting for certain repurchase agreements and expands disclosure requirements related to repurchase agreements, securities lending, repurchase-to-maturity and similar transactions. The ASU is effective for interim and annual reporting periods beginning after December 15, 2014. Adoption will have no effect on the fund’s net assets or results of operations.

In May 2015, FASB issued ASU No. 2015-07, Fair Value Measurement (Topic 820), Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent). The ASU removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value per share practical expedient and amends certain disclosure requirements for such investments. The ASU is effective for interim and annual reporting periods beginning after December 15, 2015. Adoption will have no effect on the fund’s net assets or results of operations.

The fund’s financial instruments are valued and its net asset value (NAV) per share is computed at the close of the New York Stock Exchange (NYSE), normally 4 p.m. ET, each day the NYSE is open for business.

Fair Value The fund’s financial instruments are reported at fair value, which GAAP defines as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The T. Rowe Price Valuation Committee (the Valuation Committee) has been established by the fund’s Board of Directors (the Board) to ensure that financial instruments are appropriately priced at fair value in accordance with GAAP and the 1940 Act. Subject to oversight by the Board, the Valuation Committee develops and oversees pricing-related policies and procedures and approves all fair value determinations. Specifically, the Valuation Committee establishes procedures to value securities; determines pricing techniques, sources, and persons eligible to effect fair value pricing actions; oversees the selection, services, and performance of pricing vendors; oversees valuation-related business continuity practices; and provides guidance on internal controls and valuation-related matters. The Valuation Committee reports to the Board; is chaired by the fund’s treasurer; and has representation from legal, portfolio management and trading, operations, and risk management.

Various valuation techniques and inputs are used to determine the fair value of financial instruments. GAAP establishes the following fair value hierarchy that categorizes the inputs used to measure fair value:

Level 1 – quoted prices (unadjusted) in active markets for identical financial instruments that the fund can access at the reporting date

Level 2 – inputs other than Level 1 quoted prices that are observable, either directly or indirectly (including, but not limited to, quoted prices for similar financial instruments in active markets, quoted prices for identical or similar financial instruments in inactive markets, interest rates and yield curves, implied volatilities, and credit spreads)

Observable inputs are developed using market data, such as publicly available information about actual events or transactions, and reflect the assumptions that market participants would use to price the financial instrument. Unobservable inputs are those for which market data are not available and are developed using the best information available about the assumptions that market participants would use to price the financial instrument. GAAP requires valuation techniques to maximize the use of relevant observable inputs and minimize the use of unobservable inputs. When multiple inputs are used to derive fair value, the financial instrument is assigned to the level within the fair value hierarchy based on the lowest-level input that is significant to the fair value of the financial instrument. Input levels are not necessarily an indication of the risk or liquidity associated with financial instruments at that level but rather the degree of judgment used in determining those values.

Valuation Techniques Debt securities generally are traded in the over-the-counter (OTC) market. Securities with remaining maturities of one year or more at the time of acquisition are valued at prices furnished by dealers who make markets in such securities or by an independent pricing service, which considers the yield or price of bonds of comparable quality, coupon, maturity, and type, as well as prices quoted by dealers who make markets in such securities. Securities with remaining maturities of less than one year at the time of acquisition generally use amortized cost in local currency to approximate fair value. However, if amortized cost is deemed not to reflect fair value or the fund holds a significant amount of such securities with remaining maturities of more than 60 days, the securities are valued at prices furnished by dealers who make markets in such securities or by an independent pricing service. Generally, debt securities are categorized in Level 2 of the fair value hierarchy; however, to the extent the valuations include significant unobservable inputs, the securities would be categorized in Level 3.

Equity securities listed or regularly traded on a securities exchange or in the OTC market are valued at the last quoted sale price or, for certain markets, the official closing price at the time the valuations are made. OTC Bulletin Board securities are valued at the mean of the closing bid and asked prices. A security that is listed or traded on more than one exchange is valued at the quotation on the exchange determined to be the primary market for such security. Listed securities not traded on a particular day are valued at the mean of the closing bid and asked prices for domestic securities and the last quoted sale or closing price for international securities.

For valuation purposes, the last quoted prices of non-U.S. equity securities may be adjusted to reflect the fair value of such securities at the close of the NYSE. If the fund determines that developments between the close of a foreign market and the close of the NYSE will, in its judgment, materially affect the value of some or all of its portfolio securities, the fund will adjust the previous quoted prices to reflect what it believes to be the fair value of the securities as of the close of the NYSE. In deciding whether it is necessary to adjust quoted prices to reflect fair value, the fund reviews a variety of factors, including developments in foreign markets, the performance of U.S. securities markets, and the performance of instruments trading in U.S. markets that represent foreign securities and baskets of foreign securities. The fund may also fair value securities in other situations, such as when a particular foreign market is closed but the fund is open. The fund uses outside pricing services to provide it with quoted prices and information to evaluate or adjust those prices. The fund cannot predict how often it will use quoted prices and how often it will determine it necessary to adjust those prices to reflect fair value. As a means of evaluating its security valuation process, the fund routinely compares quoted prices, the next day’s opening prices in the same markets, and adjusted prices.

Actively traded domestic equity securities generally are categorized in Level 1 of the fair value hierarchy. Non-U.S. equity securities generally are categorized in Level 2 of the fair value hierarchy despite the availability of quoted prices because, as described above, the fund evaluates and determines whether those quoted prices reflect fair value at the close of the NYSE or require adjustment. OTC Bulletin Board securities, certain preferred securities, and equity securities traded in inactive markets generally are categorized in Level 2 of the fair value hierarchy.

Investments in mutual funds are valued at the mutual fund’s closing NAV per share on the day of valuation and are categorized in Level 1 of the fair value hierarchy. Financial futures contracts are valued at closing settlement prices and are categorized in Level 1 of the fair value hierarchy. Forward currency exchange contracts are valued using the prevailing forward exchange rate and are categorized in Level 2 of the fair value hierarchy. Swaps are valued at prices furnished by independent swap dealers or by an independent pricing service and generally are categorized in Level 2 of the fair value hierarchy; however, if unobservable inputs are significant to the valuation, the swap would be categorized in Level 3. Assets and liabilities other than financial instruments, including short-term receivables and payables, are carried at cost, or estimated realizable value, if less, which approximates fair value.

Thinly traded financial instruments and those for which the above valuation procedures are inappropriate or are deemed not to reflect fair value are stated at fair value as determined in good faith by the Valuation Committee. The objective of any fair value pricing determination is to arrive at a price that could reasonably be expected from a current sale. Financial instruments fair valued by the Valuation Committee are primarily private placements, restricted securities, warrants, rights, and other securities that are not publicly traded.

Subject to oversight by the Board, the Valuation Committee regularly makes good faith judgments to establish and adjust the fair valuations of certain securities as events occur and circumstances warrant. For instance, in determining the fair value of troubled or thinly traded debt instruments, the Valuation Committee considers a variety of factors, which may include, but are not limited to, the issuer’s business prospects, its financial standing and performance, recent investment transactions in the issuer, strategic events affecting the company, market liquidity for the issuer, and general economic conditions and events. In consultation with the investment and pricing teams, the Valuation Committee will determine an appropriate valuation technique based on available information, which may include both observable and unobservable inputs. The Valuation Committee typically will afford greatest weight to actual prices in arm’s length transactions, to the extent they represent orderly transactions between market participants; transaction information can be reliably obtained; and prices are deemed representative of fair value. However, the Valuation Committee may also consider other valuation methods such as a discount or premium from market value of a similar, freely traded security of the same issuer; discounted cash flows; yield to maturity; or some combination. Fair value determinations are reviewed on a regular basis and updated as information becomes available, including actual purchase and sale transactions of the issue. Because any fair value determination involves a significant amount of judgment, there is a degree of subjectivity inherent in such pricing decisions, and fair value prices determined by the Valuation Committee could differ from those of other market participants. Depending on the relative significance of unobservable inputs, including the valuation technique(s) used, fair valued securities may be categorized in Level 2 or 3 of the fair value hierarchy.

Valuation Inputs The following table summarizes the fund’s financial instruments, based on the inputs used to determine their fair values on June 30, 2015:

There were no material transfers between Levels 1 and 2 during the six months ended June 30, 2015.

During the six months ended June 30, 2015, the fund invested in derivative instruments. As defined by GAAP, a derivative is a financial instrument whose value is derived from an underlying security price, foreign exchange rate, interest rate, index of prices or rates, or other variable; it requires little or no initial investment and permits or requires net settlement. The fund invests in derivatives only if the expected risks and rewards are consistent with its investment objectives, policies, and overall risk profile, as described in its prospectus and Statement of Additional Information. The fund may use derivatives for a variety of purposes, such as seeking to hedge against declines in principal value, increase yield, invest in an asset with greater efficiency and at a lower cost than is possible through direct investment, or to adjust portfolio duration and credit exposure. The risks associated with the use of derivatives are different from, and potentially much greater than, the risks associated with investing directly in the instruments on which the derivatives are based. The fund at all times maintains sufficient cash reserves, liquid assets, or other SEC-permitted asset types to cover its settlement obligations under open derivative contracts.

The fund values its derivatives at fair value, as described in Note 2, and recognizes changes in fair value currently in its results of operations. Accordingly, the fund does not follow hedge accounting, even for derivatives employed as economic hedges. Generally, the fund accounts for its derivatives on a gross basis. It does not offset the fair value of derivative liabilities against the fair value of derivative assets on its financial statements, nor does it offset the fair value of derivative instruments against the right to reclaim or obligation to return collateral.

The following table summarizes the fair value of the fund’s derivative instruments held as of June 30, 2015, and the related location on the accompanying Statement of Assets and Liabilities, presented by primary underlying risk exposure:

Additionally, the amount of gains and losses on derivative instruments recognized in fund earnings during the six months ended June 30, 2015, and the related location on the accompanying Statement of Operations is summarized in the following table by primary underlying risk exposure:

Counterparty Risk and Collateral The fund invests in derivatives in various markets, which expose it to differing levels of counterparty risk. Counterparty risk on exchange-traded and centrally cleared derivative contracts, such as futures, exchange-traded options, and centrally cleared swaps, is minimal because the clearinghouse provides protection against counterparty defaults. For futures and centrally cleared swaps, the fund is required to deposit collateral in an amount equal to a certain percentage of the contract value (margin requirement) and the margin requirement must be maintained over the life of the contract. Each clearing broker, in its sole discretion, may adjust the margin requirements applicable to the fund.

Derivatives, such as bilateral swaps, forward currency exchange contracts, and OTC options, that are transacted and settle directly with a counterparty (bilateral derivatives) expose the fund to greater counterparty risk. To mitigate this risk, the fund has entered into master netting arrangements (MNAs) with certain counterparties that permit net settlement under specified conditions and, for certain counterparties, also provide collateral agreements. MNAs may be in the form of International Swaps and Derivatives Association master agreements (ISDAs) or foreign exchange letter agreements (FX letters).

MNAs govern the ability to offset amounts the fund owes a counterparty against amounts the counterparty owes the fund (net settlement). Both ISDAs and FX letters generally allow net settlement in the event of contract termination and permit termination by either party prior to maturity upon the occurrence of certain stated events, such as failure to pay or bankruptcy. In addition, ISDAs specify other events, the occurrence of which would allow one of the parties to terminate. For example, a downgrade in credit rating of a counterparty would allow the fund to terminate while a decline in the fund’s net assets of more than a certain percentage would allow the counterparty to terminate. Upon termination, all bilateral derivatives with that counterparty would be liquidated and a net amount settled. ISDAs typically include collateral agreements whereas FX letters do not. Collateral requirements are determined based on the net aggregate unrealized gain or loss on all bilateral derivatives with each counterparty, subject to minimum transfer amounts that typically range from $100,000 to $250,000. Any additional collateral required due to changes in security values is transferred the next business day.

Collateral may be in the form of cash or debt securities issued by the U.S. government or related agencies. Cash and currencies posted by the fund are reflected as cash deposits in the accompanying financial statements and generally are restricted from withdrawal by the fund; securities posted by the fund are so noted in the accompanying Portfolio of Investments; both remain in the fund’s assets. Collateral pledged by counterparties is not included in the fund’s assets because the fund does not obtain effective control over those assets. For bilateral derivatives, collateral posted or received by the fund is held in a segregated account by the fund’s custodian. As of June 30, 2015, securities valued at $1,658,000 had been posted by the fund to counterparties for bilateral derivatives. As of June 30, 2015, collateral pledged by counterparties to the fund for bilateral derivatives consisted of $176,000 cash and securities valued at $279,000. As of June 30, 2015, cash of $955,000 had been posted by the fund for exchange-traded and/or centrally cleared derivatives.

Forward Currency Exchange Contracts The fund is subject to foreign currency exchange rate risk in the normal course of pursuing its investment objectives. It uses forward currency exchange contracts (forwards) primarily to protect its non-U.S. dollar-denominated securities from adverse currency movements and to gain exposure to currencies for the purposes of risk management or enhanced return. A forward involves an obligation to purchase or sell a fixed amount of a specific currency on a future date at a price set at the time of the contract. Although certain forwards may be settled by exchanging only the net gain or loss on the contract, most forwards are settled with the exchange of the underlying currencies in accordance with the specified terms. Forwards are valued at the unrealized gain or loss on the contract, which reflects the net amount the fund either is entitled to receive or obligated to deliver, as measured by the difference between the forward exchange rates at the date of entry into the contract and the forward rates at the reporting date. Appreciated forwards are reflected as assets, and depreciated forwards are reflected as liabilities on the accompanying Statement of Assets and Liabilities. Risks related to the use of forwards include the possible failure of counterparties to meet the terms of the agreements; that anticipated currency movements will not occur, thereby reducing the fund’s total return; and the potential for losses in excess of the fund’s initial investment. During the six months ended June 30, 2015, the volume of the fund’s activity in forwards, based on underlying notional amounts, was generally between 30% and 46% of net assets.

Futures Contracts The fund is subject to interest rate risk in the normal course of pursuing its investment objectives and uses futures contracts to help manage such risk. The fund may enter into futures contracts to manage exposure to interest rate and yield curve movements, security prices, foreign currencies, credit quality, and mortgage prepayments; as an efficient mean of adjusting exposure to all or part of a target market; to enhance income; as a cash management tool; or to adjust portfolio duration and credit exposure. A futures contract provides for the future sale by one party and purchase by another of a specified amount of a specific underlying financial instrument at an agreed-upon price, date, time, and place. The fund currently invests only in exchange-traded futures, which generally are standardized as to maturity date, underlying financial instrument, and other contract terms. Payments are made or received by the fund each day to settle daily fluctuations in the value of the contract (variation margin), which reflect changes in the value of the underlying financial instrument. Variation margin is recorded as unrealized gain or loss until the contract is closed. The value of a futures contract included in net assets is the amount of unsettled variation margin; net variation margin receivable is reflected as an asset and net variation margin payable is reflected as a liability on the accompanying Statement of Assets and Liabilities. Risks related to the use of futures contracts include possible illiquidity of the futures markets, contract prices that can be highly volatile and imperfectly correlated to movements in hedged security values and/or interest rates, and potential losses in excess of the fund’s initial investment. During the six months ended June 30, 2015, the volume of the fund’s activity in futures, based on underlying notional amounts, was generally between 22% and 31% of net assets.

Swaps The fund is subject to credit risk in the normal course of pursuing its investment objectives and uses swap contracts to help manage such risk. The fund may use swaps in an effort to manage exposure to changes in interest rates, inflation rates, and credit quality; to adjust overall exposure to certain markets; to enhance total return or protect the value of portfolio securities; to serve as a cash management tool; or to adjust portfolio duration and credit exposure. Swap agreements can be settled either directly with the counterparty (bilateral swap) or through a central clearinghouse (centrally cleared swap). Fluctuations in the fair value of a contract are reflected in unrealized gain or loss and are reclassified to realized gain or loss upon contract termination or cash settlement. Net periodic receipts or payments required by a contract increase or decrease, respectively, the value of the contract until the contractual payment date, at which time such amounts are reclassified from unrealized to realized gain or loss. For bilateral swaps, cash payments are made or received by the fund on a periodic basis in accordance with contract terms; unrealized gain on contracts and premiums paid are reflected as assets, and unrealized loss on contracts and premiums received are reflected as liabilities on the accompanying Statement of Assets and Liabilities. For centrally cleared swaps, payments are made or received by the fund each day to settle the daily fluctuation in the value of the contract (variation margin). Accordingly, the value of a centrally cleared swap included in net assets is the unsettled variation margin; net variation margin receivable is reflected as an asset and net variation margin payable is reflected as a liability on the accompanying Statement of Assets and Liabilities.

Credit default swaps are agreements where one party (the protection buyer) agrees to make periodic payments to another party (the protection seller) in exchange for protection against specified credit events, such as certain defaults and bankruptcies related to an underlying credit instrument, or issuer or index of such instruments. Upon occurrence of a specified credit event, the protection seller is required to pay the buyer the difference between the notional amount of the swap and the value of the underlying credit, either in the form of a net cash settlement or by paying the gross notional amount and accepting delivery of the relevant underlying credit. For credit default swaps where the underlying credit is an index, a specified credit event may affect all or individual underlying securities included in the index and will be settled based upon the relative weighting of the affected underlying security(s) within the index. Risks related to the use of credit default swaps include the possible inability of the fund to accurately assess the current and future creditworthiness of underlying issuers, the possible failure of a counterparty to perform in accordance with the terms of the swap agreements, potential government regulation that could adversely affect the fund’s swap investments, and potential losses in excess of the fund’s initial investment.

During the six months ended June 30, 2015, the volume of the fund’s activity in swaps, based on underlying notional amounts, was generally less than 1% of net assets.

Consistent with its investment objective, the fund engages in the following practices to manage exposure to certain risks and/or to enhance performance. The investment objective, policies, program, and risk factors of the fund are described more fully in the fund’s prospectus and Statement of Additional Information.

Emerging and Frontier Markets The fund may invest, either directly or through investments in T. Rowe Price institutional funds, in securities of companies located in, issued by governments of, or denominated in or linked to the currencies of emerging and frontier market countries; at period-end, approximately 26% of the fund’s net assets were invested in emerging markets and 3% in frontier markets. Frontier markets generally have economic structures that are less diverse and mature, and political systems that are less stable, than developed countries and emerging markets. These markets may be subject to greater political, economic, and social uncertainty and differing regulatory environments that may potentially impact the fund’s ability to buy or sell certain securities or repatriate proceeds to U.S. dollars. Such securities are often subject to greater price volatility, less liquidity, and higher rates of inflation than U.S. securities. Investing in frontier markets is significantly riskier than investing in other countries, including emerging markets.

Restricted Securities The fund may invest in securities that are subject to legal or contractual restrictions on resale. Prompt sale of such securities at an acceptable price may be difficult and may involve substantial delays and additional costs.

Other Purchases and sales of portfolio securities other than short-term securities aggregated $149,860,000 and $67,276,000, respectively, for the six months ended June 30, 2015.

No provision for federal income taxes is required since the fund intends to continue to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code and distribute to shareholders all of its taxable income and gains. Distributions determined in accordance with federal income tax regulations may differ in amount or character from net investment income and realized gains for financial reporting purposes. Financial reporting records are adjusted for permanent book/tax differences to reflect tax character but are not adjusted for temporary differences. The amount and character of tax-basis distributions and composition of net assets are finalized at fiscal year-end; accordingly, tax-basis balances have not been determined as of the date of this report.

The fund intends to retain realized gains to the extent of available capital loss carryforwards. Net realized capital losses may be carried forward indefinitely to offset future realized capital gains. As of December 31, 2014, the fund had $48,000 of available capital loss carryforwards.

At June 30, 2015, the cost of investments for federal income tax purposes was $369,652,000. Net unrealized loss aggregated $25,935,000 at period-end, of which $3,191,000 related to appreciated investments and $29,126,000 related to depreciated investments.

The fund is managed by T. Rowe Price Associates, Inc. (Price Associates), a wholly owned subsidiary of T. Rowe Price Group, Inc. (Price Group). The investment management and administrative agreement between the fund and Price Associates provides for an all-inclusive annual fee equal to 0.55% of the fund’s average daily net assets. The fee is computed daily and paid monthly. The all-inclusive fee covers investment management, shareholder servicing, transfer agency, accounting, and custody services provided to the fund, as well as fund directors’ fees and expenses. Interest, taxes, brokerage commissions, and extraordinary expenses are paid directly by the fund.

The fund may invest in the T. Rowe Price Reserve Investment Fund, the T. Rowe Price Government Reserve Investment Fund, or the T. Rowe Price Short-Term Reserve Fund (collectively, the Price Reserve Investment Funds), open-end management investment companies managed by Price Associates and considered affiliates of the fund. The Price Reserve Investment Funds are offered as short-term investment options to mutual funds, trusts, and other accounts managed by Price Associates or its affiliates and are not available for direct purchase by members of the public. The Price Reserve Investment Funds pay no investment management fees.

Mutual funds and other accounts managed by T. Rowe Price and its affiliates (collectively, T. Rowe Price funds) may invest in the fund; however, no T. Rowe Price fund may invest for the purpose of exercising management or control over the fund. At June 30, 2015, approximately 57% of the fund’s outstanding shares were held by T. Rowe Price funds.

A description of the policies and procedures used by T. Rowe Price funds and portfolios to determine how to vote proxies relating to portfolio securities is available in each fund’s Statement of Additional Information. You may request this document by calling 1-800-225-5132 or by accessing the SEC’s website, sec.gov.

The description of our proxy voting policies and procedures is also available on our website, troweprice.com. To access it, click on the words “Social Responsibility” at the top of our corporate homepage. Next, click on the words “Conducting Business Responsibly” on the left side of the page that appears. Finally, click on the words “Proxy Voting Policies” on the left side of the page that appears.

Each fund’s most recent annual proxy voting record is available on our website and through the SEC’s website. To access it through our website, follow the directions above to reach the “Conducting Business Responsibly” page. Click on the words “Proxy Voting Records” on the left side of that page, and then click on the “View Proxy Voting Records” link at the bottom of the page that appears.

The fund files a complete schedule of portfolio holdings with the Securities and Exchange Commission for the first and third quarters of each fiscal year on Form N-Q. The fund’s Form N-Q is available electronically on the SEC’s website (sec.gov); hard copies may be reviewed and copied at the SEC’s Public Reference Room, 100 F St. N.E., Washington, DC 20549. For more information on the Public Reference Room, call 1-800-SEC-0330.

On March 13, 2015, the fund’s Board of Directors (Board), including a majority of the fund’s independent directors, approved the continuation of the investment management agreement (Advisory Contract) between the fund and its investment advisor, T. Rowe Price Associates, Inc. (Advisor), as well as the continuation of the investment subadvisory agreement (Subadvisory Contract) that the Advisor has entered into with T. Rowe Price International Ltd (Subadvisor) on behalf of the fund. In connection with its deliberations, the Board requested, and the Advisor provided, such information as the Board (with advice from independent legal counsel) deemed reasonably necessary. The Board considered a variety of factors in connection with its review of the Advisory Contract and Subadvisory Contract, also taking into account information provided by the Advisor during the course of the year, as discussed below:

Services Provided by the Advisor and Subadvisor
The Board considered the nature, quality, and extent of the services provided to the fund by the Advisor and Subadvisor. These services included, but were not limited to, directing the fund’s investments in accordance with its investment program and the overall management of the fund’s portfolio, as well as a variety of related activities such as financial, investment operations, and administrative services; compliance; maintaining the fund’s records and registrations; and shareholder communications. The Board also reviewed the background and experience of the Advisor’s and Subadvisor’s senior management teams and investment personnel involved in the management of the fund, as well as the Advisor’s compliance record. The Board concluded that it was satisfied with the nature, quality, and extent of the services provided by the Advisor and Subadvisor.

Investment Performance of the Fund
The Board reviewed the fund’s three-month, one-year, and year-by-year returns, as well as the fund’s average annualized total returns over the three-year, five-year, and since-inception periods, and compared these returns with a wide variety of previously agreed-upon comparable performance measures and market data, including those supplied by Lipper and Morningstar, which are independent providers of mutual fund data.

On the basis of this evaluation and the Board’s ongoing review of investment results, and factoring in the relative market conditions during certain of the performance periods, the Board concluded that the fund’s performance was satisfactory.

Costs, Benefits, Profits, and Economies of Scale
The Board reviewed detailed information regarding the revenues received by the Advisor under the Advisory Contract and other benefits that the Advisor (and its affiliates, including the Subadvisor) may have realized from its relationship with the fund, including any research received under “soft dollar” agreements and commission-sharing arrangements with broker-dealers. The Board considered that the Advisor and Subadvisor may receive some benefit from soft-dollar arrangements pursuant to which research is received from broker-dealers that execute the applicable fund’s portfolio transactions. The Board received information on the estimated costs incurred and profits realized by the Advisor from managing T. Rowe Price mutual funds. The Board also reviewed estimates of the profits realized from managing the fund in particular, and the Board concluded that the Advisor’s profits were reasonable in light of the services provided to the fund.

The Board also considered whether the fund benefits under the fee levels set forth in the Advisory Contract from any economies of scale realized by the Advisor. The Board noted that, under the Advisory Contract, the fund pays the Advisor a single fee based on the fund’s average daily net assets that includes investment management services and provides for the Advisor to pay all expenses of the fund’s operations except for interest, taxes, portfolio transaction fees, and any nonrecurring extraordinary expenses that may arise. Under the Subadvisory Contract, the Advisor may pay the Subadvisor up to 60% of the advisory fee that the Advisor receives from the fund. The Board concluded that, based on the profitability data it reviewed and consistent with this single-fee structure, the Advisory Contract provided for a reasonable sharing of any benefits from economies of scale with the fund.

Fees
The Board was provided with information regarding industry trends in management fees and expenses, and the Board reviewed the fund’s single-fee structure in comparison with fees and expenses of other comparable funds based on information and data supplied by Lipper. For these purposes, the Board assumed that the fund’s management fee rate was equal to the single fee less the fund’s operating expenses. The information provided to the Board indicated that the fund’s management fee rate was at or below the median for comparable funds and the fund’s total expense ratio was below the median for comparable funds.

The Board also reviewed the fee schedules for institutional accounts and private accounts with similar mandates that are advised or subadvised by the Advisor and its affiliates. Management provided the Board with information about the Advisor’s responsibilities and services provided to institutional account clients, including information about how the requirements and economics of the institutional business are fundamentally different from those of the mutual fund business. The Board considered information showing that the mutual fund business is generally more complex from a business and compliance perspective than the institutional business and that the Advisor generally performs significant additional services and assumes greater risk in managing the fund and other T. Rowe Price mutual funds than it does for institutional account clients.

On the basis of the information provided and the factors considered, the Board concluded that the fees paid by the fund under the Advisory Contract are reasonable.

Approval of the Advisory Contract and Subadvisory Contract
As noted, the Board approved the continuation of the Advisory Contract and Subadvisory Contract. No single factor was considered in isolation or to be determinative to the decision. Rather, the Board concluded, in light of a weighting and balancing of all factors considered, that it was in the best interests of the fund and its shareholders for the Board to approve the continuation of the Advisory Contract and Subadvisory Contract (including the fees to be charged for services thereunder). The independent directors were advised throughout the process by independent legal counsel.

A code of ethics, as defined in Item 2 of Form N-CSR, applicable to its principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions is filed as an exhibit to the registrant’s annual Form N-CSR. No substantive amendments were approved or waivers were granted to this code of ethics during the registrant’s most recent fiscal half-year.

(a) Not applicable. The complete schedule of investments is included in Item 1 of this Form N-CSR.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

(a) The registrant’s principal executive officer and principal financial officer have evaluated the registrant’s disclosure controls and procedures within 90 days of this filing and have concluded that the registrant’s disclosure controls and procedures were effective, as of that date, in ensuring that information required to be disclosed by the registrant in this Form N-CSR was recorded, processed, summarized, and reported timely.

(b) The registrant’s principal executive officer and principal financial officer are aware of no change in the registrant’s internal control over financial reporting that occurred during the registrant’s second fiscal quarter covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

(a)(1) The registrant’s code of ethics pursuant to Item 2 of Form N-CSR is filed with the registrant’s annual Form N-CSR.

(2) Separate certifications by the registrant's principal executive officer and principal financial officer, pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 and required by Rule 30a-2(a) under the Investment Company Act of 1940, are attached.

(3) Written solicitation to repurchase securities issued by closed-end companies: not applicable.

(b) A certification by the registrant's principal executive officer and principal financial officer, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 and required by Rule 30a-2(b) under the Investment Company Act of 1940, is attached.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

T. Rowe Price Institutional International Funds, Inc.

	By	/s/ Edward C. Bernard
		Edward C. Bernard
		Principal Executive Officer

Date August 17, 2015

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

	By	/s/ Edward C. Bernard
		Edward C. Bernard
		Principal Executive Officer

Date August 17, 2015


	By	/s/ Catherine D. Mathews
		Catherine D. Mathews
		Principal Financial Officer

Date August 17, 2015

●	Developed market international bonds lost ground in U.S. dollar terms amid heightened volatility in global fixed income and currency markets.
●	The Institutional International Bond Fund returned -3.99% for the six-month period, outperforming the Barclays Global Aggregate ex USD Bond Index.
●	Country allocation, currency positioning, and sector selection all contributed to the fund’s outperformance of the benchmark.
●	Effective security selection is critical as the international bond market grows in size, complexity, and maturity, highlighting the importance of T. Rowe Price’s global sovereign, credit, and equity research platforms.

The date of this supplement is August 17, 2015.
	E167-041		8/17/15