Risk/Return

The Fund seeks to track the performance of a benchmark index that measures the investment return of large-capitalization growth stocks in the United States.

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

Shareholder Fees (Vanguard Mega Cap Growth Index Fund ETF) Vanguard Mega Cap Growth Index Fund	Vanguard Mega Cap Growth Index Fund - ETF Shares
Transaction Fee on Conversion to ETF Shares	0
Transaction Fee On Purchases and Sales	0
Transaction Fee On Reinvested Dividends	0

Annual Fund Operating Expenses (Vanguard Mega Cap Growth Index Fund ETF) Vanguard Mega Cap Growth Index Fund	Vanguard Mega Cap Growth Index Fund - ETF Shares
Management Expenses	0.08%
12b-1 Distribution Fee	none
Other Expenses	0.04%
Total Annual Fund Operating Expenses	0.12%

The following example is intended to help you compare the cost of investing in MegaCap Growth ETF with the cost of investing in other funds. It illustrates the hypothetical expenses that you would incur over various periods if you invest $10,000 in MegaCap Growth ETF. This example assumes that MegaCap Growth ETF provides a return of 5% a year and that total annual fund operating expenses remain as stated in the preceding table. The results apply whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or 'turns over' its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 16%.

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 of the CRSP US Mega Cap Index. The Index is a free-float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization growth stocks. 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.

An investment in the Fund could lose money over short or even long periods. You should expect the Fund's share price and total return to fluctuate within a wide range, like the fluctuations of the overall stock market. The Fund is subject to the following risks, which could affect the Fund's performance:

Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund's target index may, at times, become focused in stocks of a particular sector, category, or group of companies, which could cause the Fund to underperform the overall stock market.

Investment style risk, which is the chance that returns from large-capitalization growth stocks will trail returns from the overall stock market. Large-cap growth stocks tend to go through cycles of doing better-or worse-than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.

Because ETF Shares are traded on an exchange, they are subject to additional risks:

The Fund's ETF Shares are listed for trading on NYSE Arca and are bought and sold on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price and the NAV differ significantly. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.

Although the Fund's ETF Shares are listed for trading on NYSE Arca, it is possible that an active trading market may not be maintained.

Trading of the Fund's ETF Shares on NYSE Arca may be halted by the activation of individual or marketwide 'circuit breakers'(which halt trading for a specific period of time when the price of a particular security or overall market prices decline by a specified percentage). Trading of the Fund's ETF Shares may also be halted if (1) the shares are delisted from NYSE Arca without first being listed on another exchange or (2) NYSE Arca officials determine that such action is appropriate in the interest of a fair and orderly market or to protect investors.

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund's ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of the Fund's target index, which has investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

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 ).

Average Annual Total Returns (Vanguard Mega Cap Growth Index Fund ETF) Vanguard Mega Cap Growth Index Fund	One Year	Five Years	Since Inception
Vanguard Mega Cap Growth Index Fund - ETF Shares	17.23%	3.52%	3.89%
Vanguard Mega Cap Growth Index Fund - ETF Shares Return After Taxes on Distributions	16.94%	3.30%	3.67%
Vanguard Mega Cap Growth Index Fund - ETF Shares Return After Taxes on Distributions and Sale of Fund Shares	11.59%	2.98%	3.30%
Vanguard Mega Cap Growth Index Fund - ETF Shares Based on Market Value	17.25%	3.53%	3.90%
Vanguard Mega Cap Growth Index Fund - ETF Shares MSCI US Large Cap Growth Index	17.36%	3.61%	3.99%

Investment Objective

Fees and Expenses

Shareholder Fees (Fees paid directly from your investment)

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

Example

Expense Example, No Redemption (Vanguard Mega Cap Growth Index Fund Institutional) Vanguard Mega Cap Growth Index Fund (USD $)	1 YEAR	3 YEAR	5 YEAR	10 YEAR
Vanguard Mega Cap Growth Index Fund - Institutional Shares	9	29	51	115

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or 'turns over' its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 16%.

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 of the CRSP US Mega Cap Index. The Index is a free-float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization growth stocks. 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.

An investment in the Fund could lose money over short or even long periods. You should expect the Fund's share price and total return to fluctuate within a wide range, like the fluctuations of the overall stock market. The Fund is subject to the following risks, which could affect the Fund's performance:

Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund's target index may, at times, become focused in stocks of a particular sector, category, or group of companies, which could cause the Fund to underperform the overall stock market.

Investment style risk, which is the chance that returns from large-capitalization growth stocks will trail returns from the overall stock market. Large-cap growth stocks tend to go through cycles of doing better-or worse-than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund's Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of the Fund's target index, which has investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

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 ).

Average Annual Total Returns (Vanguard Mega Cap Growth Index Fund Institutional) Vanguard Mega Cap Growth Index Fund	One Year	Since Inception
Vanguard Mega Cap Growth Index Fund - Institutional Shares	17.25%	5.29%
Vanguard Mega Cap Growth Index Fund - Institutional Shares Return After Taxes on Distributions	17.02%	5.07%
Vanguard Mega Cap Growth Index Fund - Institutional Shares Return After Taxes on Distributions and Sale of Fund Shares	11.51%	4.51%
Vanguard Mega Cap Growth Index Fund - Institutional Shares MSCI US Large Cap Growth Index	17.36%	5.36%

Investment Objective

Fees and Expenses

Shareholder Fees (Fees paid directly from your investment)

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

Example

Expense Example, No Redemption (Vanguard Mega Cap Index Fund ETF) Vanguard Mega Cap Index Fund (USD $)	1 YEAR	3 YEAR	5 YEAR	10 YEAR
Vanguard Mega Cap Index Fund - ETF Shares	12	39	68	154

Portfolio Turnover

Primary Investment Strategies

Primary Risks

Annual Total Returns

Annual Total Returns - Vanguard Mega Cap Index Fund ETF Shares

1 The year-to-date return as of the most recent calendar quarter, which ended on March 31, 2013 was 10.29%

Average Annual Total Returns for Periods Ended December 31, 2012

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 will 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.

Risk/Return

The Fund seeks to track the performance of a benchmark index that measures the investment return of large-capitalization stocks in the United States.

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

Shareholder Fees (Vanguard Mega Cap Index Fund Institutional) Vanguard Mega Cap Index Fund	Vanguard Mega Cap Index Fund - Institutional Shares
Sales charge (load) imposed on purchases	none
Purchase Fee	none
Sales charge (load) imposed on reinvested dividends	none
Redemption Fee	none

Annual Fund Operating Expenses (Vanguard Mega Cap Index Fund Institutional) Vanguard Mega Cap Index Fund	Vanguard Mega Cap Index Fund - Institutional Shares
Management Expenses	0.05%
12b-1 Distribution Fee	none
Other Expenses	0.03%
Total Annual Fund Operating Expenses	0.08%

The following example is intended to help you compare the cost of investing in the Fund's Institutional Shares with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invest $10,000 in the Fund's shares. This example assumes that the Shares provide a return of 5% a year and that total annual fund operating expenses remain as stated in the preceding table. The results apply whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Portfolio Turnover

Primary Investment Strategies

Primary Risks

Annual Total Returns

Annual Total Returns - Vanguard Mega Cap Index Fund Institutional Shares

1 The year-to-date return as of the most recent calendar quarter, which ended on March 31, 2013 was 10.31%

Average Annual Total Returns for Periods Ended December 31, 2012

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 will 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.

Risk/Return

The Fund seeks to track the performance of a benchmark index that measures the investment return of large-capitalization value stocks in the United States.

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

Shareholder Fees (Vanguard Mega Cap Value Index Fund ETF) Vanguard Mega Cap Value Index Fund	Vanguard Mega Cap Value Index Fund - ETF Shares
Transaction Fee on Conversion to ETF Shares	0
Transaction Fee On Purchases and Sales	0
Transaction Fee On Reinvested Dividends	0

Annual Fund Operating Expenses (Vanguard Mega Cap Value Index Fund ETF) Vanguard Mega Cap Value Index Fund	Vanguard Mega Cap Value Index Fund - ETF Shares
Management Expenses	0.08%
12b-1 Distribution Fee	none
Other Expenses	0.04%
Total Annual Fund Operating Expenses	0.12%

The following example is intended to help you compare the cost of investing in MegaCap Value ETF with the cost of investing in other funds. It illustrates the hypothetical expenses that you would incur over various periods if you invest $10,000 in MegaCap Value ETF. This example assumes that MegaCap Value ETF provides a return of 5% a year and that total annual fund operating expenses remain as stated in the preceding table. The results apply whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or 'turns over' its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 17%.

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 of the CRSP US Mega Cap Index. The Index is a free-float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization value stocks. 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.

An investment in the Fund could lose money over short or even long periods. You should expect the Fund's share price and total return to fluctuate within a wide range, like the fluctuations of the overall stock market. The Fund is subject to the following risks, which could affect the Fund's performance:

Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund's target index may, at times, become focused in stocks of a particular sector, category, or group of companies, which could cause the Fund to underperform the overall stock market.

Investment style risk, which is the chance that returns from large-capitalization value stocks will trail returns from the overall stock market. Large-cap value stocks tend to go through cycles of doing better-or worse-than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.

Because ETF Shares are traded on an exchange, they are subject to additional risks:

The Fund's ETF Shares are listed for trading on NYSE Arca and are bought and sold on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price and the NAV differ significantly. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.

Although the Fund's ETF Shares are listed for trading on NYSE Arca, it is possible that an active trading market may not be maintained.

Trading of the Fund's ETF Shares on NYSE Arca may be halted by the activation of individual or marketwide 'circuit breakers'(which halt trading for a specific period of time when the price of a particular security or overall market prices decline by a specified percentage). Trading of the Fund's ETF Shares may also be halted if (1) the shares are delisted from NYSE Arca without first being listed on another exchange or (2) NYSE Arca officials determine that such action is appropriate in the interest of a fair and orderly market or to protect investors.

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund's ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of the Fund's target index, which has investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

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 ).

Average Annual Total Returns (Vanguard Mega Cap Value Index Fund ETF) Vanguard Mega Cap Value Index Fund	One Year	Five Years	Since Inception
Vanguard Mega Cap Value Index Fund - ETF Shares	14.95%	(0.29%)	(0.06%)
Vanguard Mega Cap Value Index Fund - ETF Shares Return After Taxes on Distributions	14.46%	(0.71%)	(0.48%)
Vanguard Mega Cap Value Index Fund - ETF Shares Return After Taxes on Distributions and Sale of Fund Shares	10.34%	(0.31%)	(0.12%)
Vanguard Mega Cap Value Index Fund - ETF Shares Based on Market Value	14.93%	(0.27%)	(0.06%)
Vanguard Mega Cap Value Index Fund - ETF Shares MSCI US Large Cap Value Index	15.04%	(0.27%)	(0.03%)

Investment Objective

Fees and Expenses

Shareholder Fees (Fees paid directly from your investment)

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

Example

Expense Example, No Redemption (Vanguard Mega Cap Value Index Fund Institutional) Vanguard Mega Cap Value Index Fund (USD $)	1 YEAR	3 YEAR	5 YEAR	10 YEAR
Vanguard Mega Cap Value Index Fund - Institutional Shares	8	26	45	103

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or 'turns over' its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in more taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the previous expense example, reduce the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 17%.

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 of the CRSP US Mega Cap Index. The Index is a free-float-adjusted, market-capitalization-weighted index designed to measure equity market performance of mega-capitalization value stocks. 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.

An investment in the Fund could lose money over short or even long periods. You should expect the Fund's share price and total return to fluctuate within a wide range, like the fluctuations of the overall stock market. The Fund is subject to the following risks, which could affect the Fund's performance:

Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Fund's target index may, at times, become focused in stocks of a particular sector, category, or group of companies, which could cause the Fund to underperform the overall stock market.

Investment style risk, which is the chance that returns from large-capitalization value stocks will trail returns from the overall stock market. Large-cap value stocks tend to go through cycles of doing better-or worse-than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.

An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The following bar chart and table are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund's Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of the Fund's target index, which has investment characteristics similar to those of the Fund. Keep in mind that the Fund's past performance (before and after taxes) does not indicate how the Fund will perform in the future. Updated performance information is available on our website at vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

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 ).

Average Annual Total Returns (Vanguard Mega Cap Value Index Fund Institutional) Vanguard Mega Cap Value Index Fund	One Year	Since Inception
Vanguard Mega Cap Value Index Fund - Institutional Shares	14.99%	1.72%
Vanguard Mega Cap Value Index Fund - Institutional Shares Return After Taxes on Distributions	14.49%	1.27%
Vanguard Mega Cap Value Index Fund - Institutional Shares Return After Taxes on Distributions and Sale of Fund Shares	10.37%	1.40%
Vanguard Mega Cap Value Index Fund - Institutional Shares MSCI US Large Cap Value Index	15.04%	1.71%