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During the periods shown in the bar chart, the highest return for a calendar quarter was 22.46% (quarter ended September 30, 2009 ), and the lowest return for a quarter was -31.30% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 18.16% (quarter ended September 30, 2010 ), and the lowest return for a quarter was -17.85% (quarter ended March 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 13.51% (quarter ended March 31, 2013 ), and the lowest return for a quarter was -17.44% (quarter ended September 30, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 21.04% (quarter ended September 30, 2009 ), and the lowest return for a quarter was -25.41% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 14.55% (quarter ended March 31, 2013 ), and the lowest return for a quarter was -13.15% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 21.97% (quarter ended December 31, 2010 ), and the lowest return for a quarter was -27.62% (quarter ended September 30, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 28.84% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -33.25% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 15.61% (quarter ended March 31, 2013 ), and the lowest return for a quarter was -13.74% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 21.47% (quarter ended September 30, 2009 ), and the lowest return for a quarter was -24.22% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 20.85% (quarter ended March 31, 2012 ), and the lowest return for a quarter was -25.87% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 52.06% (quarter ended September 30, 2011 ), and the lowest return for a quarter was -20.01% (quarter ended March 31, 2009 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 15.54% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -21.46% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 16.12% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -19.64% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 15.24% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -23.23% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 20.09% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -27.03% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 52.05% (quarter ended September 30, 2011 ), and the lowest return for a quarter was -20.01% (quarter ended March 31, 2009 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 15.55% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -13.36% (quarter ended September 30, 2011 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 16.08% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -16.97% (quarter ended March 31, 2009 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 15.27% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -12.60% (quarter ended June 30, 2010 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 18.25% (quarter ended March 31, 2012 ), and the lowest return for a quarter was -21.62% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 27.11% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -23.16% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 20.09% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -27.09% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 18.23% (quarter ended March 31, 2012 ), and the lowest return for a quarter was -21.69% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 27.03% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -23.22% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 20.09% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -27.09% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 22.44% (quarter ended September 30, 2009 ), and the lowest return for a quarter was -31.31% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 18.20% (quarter ended September 30, 2010 ), and the lowest return for a quarter was -17.88% (quarter ended March 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 18.23% (quarter ended March 31, 2012 ), and the lowest return for a quarter was -21.69% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 13.53% (quarter ended March 31, 2013 ), and the lowest return for a quarter was -17.44% (quarter ended September 30, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 21.06% (quarter ended September 30, 2009 ), and the lowest return for a quarter was -25.39% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 14.54% (quarter ended March 31, 2013 ), and the lowest return for a quarter was -13.18% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 21.95% (quarter ended December 31, 2010 ), and the lowest return for a quarter was -27.64% (quarter ended September 30, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 28.92% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -33.25% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 15.62% (quarter ended March 31, 2013 ), and the lowest return for a quarter was -13.73% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 21.45% (quarter ended September 30, 2009 ), and the lowest return for a quarter was -24.24% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 20.85% (quarter ended March 31, 2012 ), and the lowest return for a quarter was -25.87% (quarter ended December 31, 2008 ).

During the periods shown in the bar chart, the highest return for a calendar quarter was 27.03% (quarter ended June 30, 2009 ), and the lowest return for a quarter was -23.22% (quarter ended December 31, 2008 ).

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Annual Total Returns - Vanguard Materials Index Fund ETF Shares

Annual Total Returns - Vanguard Telecommunication Services Index Fund ETF Shares

Annual Total Returns - Vanguard Utilities Index Fund ETF Shares

Annual Total Returns - Vanguard Consumer Discretionary Index Fund ETF Shares

Annual Total Returns - Vanguard Consumer Staples Index Fund ETF Shares

Annual Total Returns - Vanguard Energy Index Fund ETF Shares

Annual Total Returns - Vanguard Financials Index Fund ETF Shares

Annual Total Returns - Vanguard Health Care Index Fund ETF Shares

Annual Total Returns - Vanguard Industrials Index Fund ETF Shares

Annual Total Returns - Vanguard Information Technology Index Fund ETF Shares

Annual Total Returns - Vanguard Extended Duration Treasury Index Fund ETF Shares

Annual Total Returns - Vanguard Mega Cap Index Fund ETF Shares

Annual Total Returns - Vanguard Mega Cap Value Index Fund ETF Shares

Annual Total Returns - Vanguard Mega Cap Growth Index Fund ETF Shares

Annual Total Returns - Vanguard FTSE Social Index Fund Institutional Shares

Annual Total Returns - Vanguard Extended Duration Treasury Index Fund Institutional Shares

Annual Total Returns - Vanguard Mega Cap Index Fund Institutional Shares

Annual Total Returns - Vanguard Mega Cap Value Index Fund Institutional Shares

Annual Total Returns - Vanguard Mega Cap Growth Index Fund Institutional Shares

Annual Total Returns - Vanguard U.S. Growth Fund Admiral Shares

Annual Total Returns - Vanguard International Growth Fund Admiral Shares

Annual Total Returns - Vanguard FTSE Social Index Fund Investor Shares

Annual Total Returns - Vanguard U.S. Growth Fund Investor Shares

Annual Total Returns - Vanguard International Growth Fund Investor Shares

Annual Total Returns - Vanguard FTSE Social Index Fund Investor Shares

Annual Total Returns - Vanguard Materials Index Fund Admiral Shares

Annual Total Returns - Vanguard Telecommunication Services Index Fund Admiral Shares

Annual Total Returns - Vanguard U.S. Growth Fund Investor Shares

Annual Total Returns - Vanguard Utilities Index Fund Admiral Shares

Annual Total Returns - Vanguard Consumer Discretionary Index Fund Admiral Shares

Annual Total Returns - Vanguard Consumer Staples Index Fund Admiral Shares

Annual Total Returns - Vanguard Energy Index Fund Admiral Shares

Annual Total Returns - Vanguard Financials Index Fund Admiral Shares

Annual Total Returns - Vanguard Health Care Index Fund Admiral Shares

Annual Total Returns - Vanguard Industrials Index Fund Admiral Shares

Annual Total Returns - Vanguard Information Technology Index Fund Admiral Shares

Annual Total Returns - Vanguard International Growth Fund Investor Shares

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Example

Examples

Example

Examples

Example

Examples

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The following table describes the fees and expenses you may pay if you buy and hold ETF Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Institutional Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Institutional Shares or Institutional Plus Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Institutional Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Admiral Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Investor Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Admiral Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Investor Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Admiral Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Investor Shares or Admiral Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Admiral Shares of the Fund.

The following table describes the fees and expenses you may pay if you buy and hold Investor Shares or Admiral Shares of the Fund.

[rr_IndexNoDeductionForFeesExpensesTaxes]

(reflect no deduction for fees, expenses, or taxes)

(reflects no deduction for fees, expenses, or taxes)

(reflect no deduction for fees, expenses, or taxes)

(reflects no deduction for fees, expenses, or taxes)

(reflect no deduction for fees, expenses, or taxes)

(reflect no deduction for fees or expenses)

(reflect no deduction for fees, expenses, or taxes)

(reflect no deduction for fees or expenses)

(reflect no deduction for fees, expenses, or taxes)

(reflects no deduction for fees, expenses, or taxes)

(reflect no deduction for fees, expenses, or taxes)

(reflects no deduction for fees, expenses, or taxes)

(reflect no deduction for fees, expenses, or taxes)

(reflect no deduction for fees or expenses)

(reflect no deduction for fees, expenses, or taxes)

(reflect no deduction for fees or expenses)

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Investment Objective

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Annual Fund Operating Expenses (Expenses that you pay each year as a percentage of the value of your investment)

[rr_PerformanceAvailabilityPhone]

800-662-7447

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The following bar chart and table are intended to help you understand the risks of investing in the Fund.

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Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are shown only for the Investor Shares and may differ for each share class. After-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. Please note that after-tax returns are shown only for the Investor Shares and may differ for each share class. After-tax returns are not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. Also, figures captioned Return After Taxes on Distributions and Sale of Fund Shares may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.

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Average Annual Total Returns for Periods Ended December 31, 2013

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Please note that after-tax returns are shown only for the Investor Shares and may differ for each share class.

Please note that after-tax returns are shown only for the Admiral Shares and may differ for each share class.

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When after-tax returns are calculated, it is assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption.

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[rr_ProspectusDate]

Dec. 23, 2014

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An investment in the Fund could lose money over short or even long periods.

[rr_RiskNondiversifiedStatus]

The Fund is considered nondiversified, which means that it may invest a greater percentage of its assets in the securities of a small number of issuers as compared with other mutual funds.

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Risk/Return

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The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Materials 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the materials sector, as classified under the Global Industry Classification Standard (GICS). The GICS materials sector is made up of companies in a wide range of commodity-related manufacturing industries. Included within this sector are companies that manufacture chemicals, construction materials, glass, paper, forest products, and related packaging products, as well as metals, minerals, and mining companies, including producers of steel.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Telecommunication Services 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the telecommunication services sector, as classified under the Global Industry Classification Standard (GICS). The GICS telecommunication services sector is made up of companies that provide communications services primarily through fixed-line, cellular, wireless, high-bandwidth, and/or fiber-optic cable networks.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Utilities 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the utilities sector, as classified under the Global Industry Classification Standard (GICS). The GICS utilities sector is made up of electric, gas, and water utility companies, as well as companies that operate as independent producers and/or distributors of power. The sector includes both nuclear and nonnuclear facilities.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the Morgan Stanley Capital InternationalMSCI U.S. Investable Market Consumer Discretionary 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the consumer discretionary sector, as classified under the Global Industry Classification Standard (GICS). The GICS consumer discretionary sector is made up of those manufacturing and service industries that tend to be the most sensitive to economic cycles. Its manufacturing segment includes the following industries: automotive, household durable goods, textiles and apparel, and leisure equipment. The services segment includes hotels, restaurants and other leisure facilities, media production and services, and consumer retailing.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Consumer Staples 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the consumer staples sector, as classified under the Global Industry Classification Standard (GICS). The GICS consumer staples sector is made up of companies whose businesses are less sensitive to economic cycles. It includes manufacturers and distributors of food, beverages, and tobacco, as well as producers of nondurable household goods and personal products. It also includes food and drug retailing companies as well as consumer supercenters.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Energy 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the energy sector, as classified under the Global Industry Classification Standard (GICS). The GICS energy sector is made up of companies whose businesses are dominated by either of the following activities: the construction or provision of oil rigs, drilling equipment, and other energy-related equipment and services (such as seismic data collection) or companies engaged in the exploration, production, marketing, refining, and/or transportation of oil and gas products.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Financials 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the financials sector, as classified under the Global Industry Classification Standard (GICS). The GICS financials sector is made up of companies involved in activities such as banking, mortgage finance, consumer finance, specialized finance, investment banking and brokerage, asset management and custody, corporate lending, insurance, financial investment, and real estate (including real estate investment trusts).

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Health Care 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the health care sector, as classified under the Global Industry Classification Standard (GICS). The GICS health care sector is made up of two main industry groups. The first group includes companies that manufacture health care equipment and supplies or provide health care-related services (such as distributors of health care products, providers of basic health care services, and owners and operators of health care facilities and organizations). The second group includes companies primarily involved in the research, development, production, and marketing of pharmaceuticals and biotechnology products.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Industrials 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the industrials sector, as classified under the Global Industry Classification Standard (GICS). The GICS industrials sector is made up of companies whose businesses are dominated by one of the following activities: the manufacture and distribution of capital goods (including aerospace and defense, construction, engineering and building products, electrical equipment, and industrial machinery); the provision of commercial services and supplies (including printing, employment, environmental, and office services); or the provision of transportation services (including airlines, couriers, marine, road, and rail) and transportation infrastructure.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the MSCI US Investable Market Index (IMI)/Information Technology 25/50, an index made up of stocks of large, mid-size, and small U.S. companies within the information technology sector, as classified under the Global Industry Classification Standard (GICS). The GICS information technology sector is made up of companies in the following three general areas: technology software and services, including companies that primarily develop software in various fields (such as the internet, applications, systems, database management, and/or home entertainment) and companies that provide information technology consulting and services, data processing, and outsourced services; technology hardware and equipment, including manufacturers and distributors of communications equipment, computers and peripherals, electronic equipment, and related instruments; and semiconductors and semiconductor equipment manufacturers.

The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the Barclays U.S. Treasury STRIPS 20-30 Year Equal Par Bond Index. This Index includes zero-coupon U.S. Treasury securities (Treasury STRIPS), which are backed by the full faith and credit of the U.S. government, with maturities ranging from 20 to 30 years. A Treasury STRIP represents a single coupon payment, or a single principal payment, from a U.S. Treasury security that has been 'stripped' into separately tradable components.

The Fund invests by sampling the Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Index in terms of key risk factors, including duration, cash flow, and other characteristics. All of the Fund's investments will be selected through the sampling process, and under normal circumstances, at least 80% of the Fund's assets will be invested in U.S. Treasury securities held in the Index. The Fund maintains a dollar-weighted average maturity consistent with that of the Index, which generally ranges between 20 and 30 years. The Fund is expected to have a duration that is greater than 20 years.

The Fund employs an indexing investment approach designed to track the performance of the CRSP US Mega Cap Index. The Index is a float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization stocks in the United States. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the CRSP US Mega Cap Value Index, which represents the value companies, as determined by the index sponsor, of the CRSP US Mega Cap Index. The Index is a float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization value stocks in the United States. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the CRSP US Mega Cap Growth Index, which represents the growth companies, as determined by the index sponsor, of the CRSP US Mega Cap Index. The Index is a float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization growth stocks in the United States. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the FTSE4Good US Select Index. The Index is composed of the stocks of companies that have been screened for certain social and environmental criteria by the Index sponsor, which is independent of Vanguard. The Index is market-capitalization weighted and includes primarily large- and mid-cap U.S. stocks that have been screened for certain criteria related to the environment, human rights, health and safety, labor standards, and diversity. The Index excludes companies involved with weapons, tobacco, gambling, alcohol, adult entertainment, and nuclear power. The Fund attempts to replicate the Index by investing all, or substantially all, of its assets in the stocks that make up the Index.

The Fund employs an indexing investment approach designed to track the performance of the Barclays U.S. Treasury STRIPS 20-30 Year Equal Par Bond Index. This Index includes zero-coupon U.S. Treasury securities (Treasury STRIPS), which are backed by the full faith and credit of the U.S. government, with maturities ranging from 20 to 30 years. A Treasury STRIP represents a single coupon payment, or a single principal payment, from a U.S. Treasury security that has been 'stripped' into separately tradable components.

The Fund invests by sampling the Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Index in terms of key risk factors, including duration, cash flow, and other characteristics. All of the Fund's investments will be selected through the sampling process, and under normal circumstances, at least 80% of the Fund's assets will be invested in U.S. Treasury securities held in the Index. The Fund maintains a dollar-weighted average maturity consistent with that of the Index, which generally ranges between 20 and 30 years. The Fund is expected to have a duration that is greater than 20 years.

The Fund employs an indexing investment approach designed to track the performance of the CRSP US Mega Cap Index. The Index is a float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization stocks in the United States. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the CRSP US Mega Cap Value Index, which represents the value companies, as determined by the index sponsor, of the CRSP US Mega Cap Index. The Index is a float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization value stocks in the United States. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund employs an indexing investment approach designed to track the performance of the CRSP US Mega Cap Growth Index, which represents the growth companies, as determined by the index sponsor, of the CRSP US Mega Cap Index. The Index is a float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization growth stocks in the United States. The Fund attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index.

The Fund invests mainly in large-capitalization stocks of U.S. companies considered to have above-average earnings growth potential and reasonable stock prices in comparison with expected earnings. Under normal circumstances, at least 80% of the Fund's assets will be invested in securities issued by U.S. companies. The Fund uses multiple investment advisors.

The Fund invests predominantly in the stocks of companies located outside the United States and is expected to diversify its assets in countries across developed and emerging markets. In selecting stocks, the Fund's advisors evaluate foreign markets around the world and choose large-, mid-, and small-capitalization companies considered to have above-average growth potential. The Fund uses multiple investment advisors.