Bond Market Index Fund (Prospectus Summary) | Bond Market Index Fund

Bond Market Index Fund

Objective:

The Fund seeks to provide current income.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold
shares of the Fund.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Bond Market Index Fund Class J Shares
Maximum Deferred Sales Charge (Load) (as a percentage of dollars subject to charge)	1.00%

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

Annual Fund Operating Expenses		Bond Market Index Fund Class J Shares
Management Fees		0.25%
Distribution and/or Service (12b-1) Fees		0.45%
Other Expenses	[1]	0.35%
Total Annual Fund Operating Expenses		1.05%
Fee Waiver	[2]	0.20%
Total Annual Fund Operating Expenses After Fee Waiver		0.85%

Example

This Example is intended to help you compare the cost of investing in the Fund
with the cost of investing in other mutual funds.
  
The Example assumes that you invest $10,000 in the Fund for the time periods
indicated and then redeem all of your shares at the end of those periods. The
Example also assumes that your investment has a 5% return each year and that the
Fund's operating expenses remain the same. Although your actual costs may be
higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)	Expense Example, With Redemption, 1 Year	Expense Example, With Redemption, 3 Years	Expense Example, With Redemption, 5 Years	Expense Example, With Redemption, 10 Years
Bond Market Index Fund Class J Shares	187	314	560	1,265

You would pay the following expenses if you did not redeem your shares:

Expense Example, No Redemption (USD $)	Expense Example, No Redemption, 1 Year	Expense Example, No Redemption, 3 Years	Expense Example, No Redemption, 5 Years	Expense Example, No Redemption, 10 Years
Bond Market Index Fund Class J Shares	87	314	560	1,265

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 example, affect the Fund's performance.
During the most recent fiscal year, the Fund's annualized portfolio turnover
rate was 84.6% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets,
plus borrowings for investment purposes, in debt securities held by the Barclays
Capital U.S. Aggregate Bond Index (the "Index") at the time of purchase. The
Index is composed of investment grade, fixed rate debt issues, including
government, corporate, asset-backed, and mortgage-backed securities, with
maturities of one year or more. The Fund employs a passive investment approach
designed to attempt to track the performance of the Index. Under normal
circumstances, the Fund maintains an average portfolio duration that is in line
with the duration of the Barclays Capital U.S. Aggregate Bond Index, which as of
August 31, 2011 was 5.05 years.

Principal Risks

The Fund may be an appropriate investment for investors interested in investing
in a fixed-income mutual fund and preferring a passive, rather than active,
management style.
  
The value of your investment in the Fund changes with the value of the Fund's
investments. Many factors affect that value, and it is possible to lose money by
investing in the Fund. 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 principal risks of investing in the Fund, in
alphabetical order, are:
  
Fixed-Income Securities Risk. Fixed-income securities are subject to interest
rate risk and credit quality risk. The market value of fixed-income securities
generally declines when interest rates rise, and an issuer of fixed-income
securities could default on its payment obligations.
  
Index Fund Investment Risk. More likely than not, an index fund will not provide
investment performance that matches the index performance due to cashflows and
the fees and expenses of the fund.

Portfolio Duration Risk. Portfolio duration is a measure of the expected life of
a fixed-income security and its sensitivity to changes in interest rates. The
longer a fund's average portfolio duration, the more sensitive the fund will be
to changes in interest rates.
  
Prepayment Risk. Unscheduled prepayments on mortgage-backed and asset-backed
securities may have to be reinvested at lower rates. A reduction in prepayments
may increase the effective maturities of these securities, exposing them to the
risk of decline in market value over time (extension risk).
  
Real Estate Securities Risk. Real estate securities are subject to the risks
associated with direct ownership of real estate, including declines in value,
adverse economic conditions, increases in expenses, regulatory changes and
environmental problems.
  
Risk of Being an Underlying Fund. An underlying fund of a fund of funds may
experience relatively large redemptions or investments as the fund of funds
periodically reallocates or rebalances its assets. These transactions may cause
the underlying fund to sell portfolio securities to meet such redemptions, or to
invest cash from such investments, at times it would not otherwise do so, and
may as a result increase transaction costs and adversely affect underlying fund
performance.

U.S. Government Securities Risk. Yields available from U.S. government
securities are generally lower than yields from many other fixed-income
securities.
  
U.S. Government Sponsored Securities Risk. Securities issued by U.S.
government-sponsored or -chartered enterprises such as the Federal Home Loan
Mortgage Corporation, the Federal National Mortgage Association, and the Federal
Home Loan Banks are not issued or guaranteed by the U.S. Treasury.

Performance

The following information provides an indication of the risks of investing in
the Fund. The bar chart shows the investment returns of the Fund's Class J
shares for each full calendar year of operations for 10 years (or, if shorter,
the life of the Fund). These annual returns do not reflect sales charges; if
they did, returns would be lower. The table shows, for Class J shares of the
Fund and for the last one, five, and ten calendar year periods (or, if shorter,
the life of the Fund), how the Fund's average annual total returns compare to
the returns of one or more broad-based market indices. Past performance (before
and after taxes) is not necessarily an indication of how the Fund will perform
in the future. You may get updated performance information online at
www.principalfunds.com or by calling 1-800-222-5852.
  
Life of Fund returns are measured from the date the Class J shares were first
sold December 30, 2009.

Total Returns as of December 31 each year (Class J shares)

^[1]

Highest return for a quarter during the period of the bar chart above:  Q3 '11       3.60%
Lowest return for a quarter during the period of the bar chart above:   Q4 '10      -1.49%

Average Annual Total Returns For the periods ended December 31, 2011

Average Annual Total Returns Bond Market Index Fund	Average Annual Returns, Label	Average Annual Returns, 1 Year	Average Annual Returns, Since Inception
Class J Shares	Class J Return Before Taxes	5.77%	5.72%
Class J Shares After Taxes on Distributions	Class J Return After Taxes on Distributions	5.06%	5.08%
Class J Shares After Taxes on Distributions and Sales	Class J Return After Taxes on Distribution and Sale of Fund Shares	3.75%	4.51%
Barclays Capital Aggregate Bond Index	Barclays Capital Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes)	7.84%	7.09%

After-tax returns are calculated using the historical highest individual federal
marginal income tax rates and do not reflect the impact of state and local taxes.
Actual after-tax returns depend on an investor's tax situation and may differ from
those shown. The after-tax returns shown are not relevant to investors who hold
their Fund shares through tax-deferred arrangements, such as 401(k) plans or
individual retirement accounts.

[1] Expense information has been restated to reflect current fees. Certain Other Expenses of the Fund have increased effective November 1, 2011.

[2] Effective January 1, 2012, Principal Funds Distributor, Inc. ("the Distributor") has contractually agreed to limit the Distribution Fees attributable to Class J through December 31, 2012. The limit will maintain the level of Distribution Fees not to exceed 0.25%. It is expected that the expense limit will continue through the period disclosed; however, Principal Funds, Inc. and the Distributor, the parties to the agreement, may agree to terminate the expense limit prior to the end of the period.

[1] The year-to-date return as of March 31, 2012 was 0.09% for Class J shares.