Vanguard Inflation-Protected Securities Fund Summary Prospectus

April 27, 2010

Investor Shares for Participants

Vanguard Inflation-Protected Securities Fund Investor Shares (VIPSX)

The Fund’s statutory Prospectus and Statement of Additional Information dated April 27, 2010, and financial highlights information from the most recent shareholder report are incorporated into and made part of this Summary Prospectus by reference.

Before you invest, you may want to review the Fund’s Prospectus, which contains more information about the Fund and its risks. You can find the Fund’s Prospectus and other information about the Fund online at www.vanguard.com/prospectus. You can also get this information at no cost by calling 800-523-1188 or by sending an e-mail request to online@vanguard.com.

The Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

Investment Objective

The Fund seeks to provide inflation protection and income consistent with investment in inflation-indexed securities

Fees and Expenses

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

Shareholder Fees
(Fees paid directly from your investment)
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

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

Management Expenses	0.22%
12b-1 Distribution Fee	None
Other Expenses	0.03%
Total Annual Fund Operating Expenses	0.25%

Example

The following example is intended to help you compare the cost of investing in the Fund’s Investor 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 operating expenses remain the same. 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:

1 Year	3 Years	5 Years	10 Years
$26	$80	$141	$318

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Portfolio Turnover

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 higher 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, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 14% of the average value of its portfolio.

Primary Investment Strategies

The Fund invests at least 80% of its assets in inflation-indexed bonds issued by the U.S. government, its agencies and instrumentalities, and corporations. The Fund may invest in bonds of any maturity; however, its dollar-weighted average maturity is expected to be in the range of 7 to 20 years. At a minimum, all bonds purchased by the Fund will be rated “investment-grade.”

Primary Risks

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 bond market. The Fund’s performance could be hurt by:

• Income fluctuations. The Fund’s quarterly income distributions are likely to fluctuate considerably more than the income distributions of a typical bond fund. Income fluctuations associated with changes in interest rates are expected to be low; however, income fluctuations associated with changes in inflation are expected to be high. Overall, investors can expect income fluctuations to be high for the Fund.

• Interest rate risk, which is the chance that bond prices overall will decline because of rising interest rates. Interest rate risk is expected to be moderate for the Fund.

• Manager risk, which is the chance that poor security selection or focus on securities in a particular sector, category, or group of companies will cause the Fund to underperform relevant benchmarks or other funds with a similar investment objective.

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.

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Annual Total Returns

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 Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns compare with those of a relevant market index. Keep in mind that the Fund’s past performance does not indicate how the Fund will perform in the future. Updated performance information is available on our website at www.vanguard.com/performance or by calling Vanguard toll-free at 800-662-7447.

Annual Total Returns—Investor Shares

During the periods shown in the bar chart, the highest return for a calendar quarter was 7.96% (quarter ended September 30, 2002), and the lowest return for a quarter was –3.89% (quarter ended December 31, 2008).

Average Annual Total Returns for Periods Ended December 31, 2009

			Since
			Inception
			(Jun. 29,
	1 Year	5 Years	2000)
Vanguard Inflation-Protected Securities Fund
Investor Shares	10.80%	4.36%	7.14%
Barclays Capital U.S. Treasury Inflation Protected
Securities Index
(reflects no deduction for fees or expenses)	11.41%	4.63%	7.38%

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Investment Advisor
The Vanguard Group, Inc.

Portfolio Managers

John W. Hollyer, CFA, Principal of Vanguard. He has co-managed the Fund since its inception in 2000.

Kenneth E. Volpert, CFA, Principal of Vanguard and head of Vanguard’s Taxable Bond Group. He has co-managed the Fund since its inception in 2000.

Tax Information

The Fund’s distributions will be reinvested in additional Fund shares and accumulate on a tax-deferred basis if you are investing through an employer-sponsored retirement or savings plan. You will not owe taxes on these distributions until you begin withdrawals from the plan. You should consult your plan administrator, your plan’s Summary Plan Description, or your tax advisor about the tax consequences of plan withdrawals.

Payments to Financial Intermediaries

The Fund and its investment advisor do not pay financial intermediaries for sales of Fund shares or related services.

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Vanguard Inflation-Protected Securities Fund Investor Shares—Fund Number 119

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© 2010 The Vanguard Group, Inc. All rights reserved.
Vanguard Marketing Corporation, Distributor.

SPI119 042010