Risk/Return:

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Investment Objective

Expense Heading [Optional Text]

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Fees and Expenses of the Portfolio

Shareholder Fees Caption [Optional Text]

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Shareholder Fees (fees paid directly from your investment)

Portfolio Turnover [Heading]

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PORTFOLIO TURNOVER

Portfolio Turnover, Rate

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114.00%

Expense Example Narrative [Text Block]

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This Example is meant to help you compare the cost of investing in the Portfolio with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. The costs for the Portfolio reflect the net expenses of the Portfolio that result from the contractual expense waiver in the first year only. Although your actual costs may be higher or lower, based on these assumptions your costs whether you redeem or hold your shares would be:

Strategy Narrative [Text Block]

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The Selective State Municipal Bond Portfolio seeks its investment objective by investing primarily in a universe of investment grade municipal securities, the interest on which is exempt from regular federal income tax. Municipal securities in which the Portfolio may invest include, among others, revenue bonds, general obligation bonds, industrial development bonds, municipal lease obligations, commercial paper, variable rate demand obligations and other instruments (including participation interests in such securities) issued by or on behalf of the states, territories, and possessions of the United States (including the District of Columbia) and their political subdivisions, agencies, and instrumentalities (“state issuers”). As of the date of this prospectus, Dimensional Fund Advisors LP (the “Advisor”) expects to emphasize investments in obligations issued by or on behalf of: (i) state issuers with no personal income tax (e.g., Wyoming, Washington, Tennessee, Texas, South Dakota, Nevada, New Hampshire, Florida, and Alaska); (ii) state issuers that generally tax income earned from both in-state and out-of-state municipal securities (e.g., Iowa, Illinois, and Wisconsin); (iii) state issuers that do not tax income earned from in-state municipal securities and certain out-of-state municipal securities (e.g., Utah) and (iv) state issuers that do not tax income earned from in-state or any out-of-state municipal securities. From time to time, the Advisor may emphasize investments in additional state issuers or reduce the Portfolio’s emphasis on certain state issuers without notice to shareholders. The interest on the municipal securities purchased by the Portfolio, in the opinion of bond counsel for the issuers and under current tax law, is exempt from federal income tax (i.e., excludable from gross income for individuals for federal income tax purposes but not necessarily exempt from state or local taxes). As a fundamental investment policy, under normal market conditions, the Portfolio will invest at least 80% of its net assets in municipal securities that pay interest exempt from federal income tax. The Portfolio does not currently intend to invest its assets in municipal securities whose interest is subject to the federal alternative minimum tax.

Generally, the Selective State Municipal Bond Portfolio will acquire obligations that mature within twenty years from the date of settlement, and in variable rate demand obligations with longer maturities. Under normal circumstances, the Portfolio will maintain a weighted average duration of more than three years but less than five years. In making purchase decisions, if the expected term premium is greater for longer-term securities in the eligible maturity range, the Advisor will focus investment in the longer-term area, otherwise, the Portfolio will focus investment in the shorter-term area of the eligible maturity range. If a security has been or is expected to be redeemed by the issuer at a date prior to the stated final maturity date for the purposes of the above duration restriction, the early redemption date shall be considered the maturity date regardless of the stated final maturity. If a security's coupon or interest rate is periodically reset, the reset date will be considered for the purposes of the above duration restriction. Duration is a measure of the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.

At least 75% of the assets of the Selective State Municipal Bond Portfolio will be invested in municipal securities that, at the time of purchase, are rated in the top three credit-rating categories (e.g., Aaa, Aa and A for Moody’s Ratings (“Moody’s”) or AAA, AA and A for S&P Global Ratings (“S&P”) or Fitch Ratings Ltd. (“Fitch”), or an equivalent rating assigned by another nationally recognized statistical rating organization, or that are unrated but have been determined by the Advisor to be of comparable quality). No more than 25% of the Portfolio’s assets will be invested in municipal securities that, at the time of purchase, are rated in the lowest quarter of the investment grade spectrum (e.g., rated Baa1 to Baa3 (by Moody’s) or BBB+ to BBB- (by S&P or Fitch), or an equivalent rating assigned by another nationally recognized statistical rating organization, or that are unrated but have been determined by the Advisor to be of comparable quality). The fixed income securities in which the Portfolio invests are considered investment grade at the time of purchase.

Municipal securities are often issued to obtain funds for various public purposes, including the construction of a wide range of public facilities, such as bridges, highways, housing, hospitals, mass transportation facilities, schools, streets and public utilities, such as water and sewer works. Municipal securities include municipal leases, certificates of participation, municipal obligation components and municipal custody receipts. The Selective State Municipal Bond Portfolio may invest more than 25% of its assets in municipal securities issued to finance projects in a particular segment of the bond market including, but not limited to, health care, housing, education, utilities, and transportation. The Portfolio also may invest more than 25% of its assets in industrial development bonds.

The Selective State Municipal Bond Portfolio may (1) purchase certain municipal securities that are insured, (2) invest in municipal securities secured by mortgages on single-family homes and multi-family projects, (3) invest in pre-refunded municipal securities, (4) purchase tax-exempt municipal securities on a “when-issued” basis, and (5) use derivatives, such as fixed income related futures and options contracts, credit default swaps and interest rate swaps,

to hedge against changes in interest rates. The Portfolio may also invest in exchange-traded funds (ETFs) to gain exposure to the municipal bond market pending investment in municipal bonds. The Portfolio may also invest in money market funds. The Portfolio also may purchase or sell futures contracts and options on futures contracts, to hedge its interest rate exposure or for non-hedging purposes, such as a substitute for direct investment or to increase or decrease market exposure based on actual or expected cash inflows to or outflows from the Portfolio.

Although the Selective State Municipal Bond Portfolio attempts to invest all of its assets in tax-exempt securities, it is possible, although not anticipated, that a portion of its assets may be invested in securities that pay taxable interest, including interest that may be subject to the federal alternative minimum tax. These investments could generate taxable income for shareholders.

Performance Narrative [Text Block]

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The bar chart and table immediately following illustrate the variability of the Portfolio’s returns and are meant to provide some indication of the risks of investing in the Portfolio. The bar chart shows the changes in the Portfolio’s performance from year to year. The table illustrates how annualized returns for certain periods, both before and after taxes, compare with those of a broad measure of market performance. The table also includes the performance of an additional index with a similar investment universe as the Portfolio. The Portfolio’s past performance (before and after taxes) is not an indication of future results. Updated performance information for the Portfolio can be obtained by visiting https://www.dimensional.com/us-en/funds.

The after-tax returns presented in the table for the Portfolio 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 in the table. In addition, the after-tax returns shown are not relevant to investors who hold shares of the Portfolio through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts.

Performance Availability Website Address [Text]

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https://www.dimensional.com/us-en/funds

Bar Chart [Heading]

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DFA Selective State Municipal Bond Portfolio Institutional Class Shares —Total Returns

Index No Deduction for Fees, Expenses, or Taxes [Text]

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

Performance Table Not Relevant to Tax Deferred

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In addition, the after-tax returns shown are not relevant to investors who hold shares of the Portfolio through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts.

Risk/Return:

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Risk [Text Block]

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Because the value of your investment in the Portfolio will fluctuate, there is the risk that you will lose money.

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Risk [Text Block]

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Market Risk: Even a long-term investment approach cannot guarantee a profit. Economic, market, environmental, political, and issuer-specific conditions and events will cause the value of securities, and a fund that owns them, to rise or fall.

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Risk [Text Block]

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Credit Risk: Credit risk is the risk that the issuer of a security, including a governmental entity, may be unable to make interest payments and/or repay principal when due. A downgrade to an issuer’s credit rating or a perceived change in an issuer’s financial strength may affect a security’s value, and thus, impact the performance of a fund holding such securities. The ability of a municipal securities issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer.

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Risk [Text Block]

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Call Risk: Call risk is the risk that during periods of falling interest rates, an issuer will call or repay a higher-yielding fixed income security before its maturity date, forcing a fund to reinvest in fixed income securities with lower interest rates than the original obligations.

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Risk [Text Block]

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Municipal Securities Risk: The risk of a municipal security generally depends on the financial and credit status of the issuer. Municipal securities can be significantly affected by political, regulatory or economic changes, including changes made in the law after issuance of the securities, as well as uncertainties in the municipal market related to taxation, legislative changes or the rights of municipal security holders, including in connection with an issuer’s insolvency. The municipal securities market can be susceptible to increases in volatility and decreases in liquidity. The secondary market for certain municipal securities tends to be less well developed or liquid than many other securities markets, which may adversely affect a fund's ability to sell such municipal securities at attractive prices. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. In addition,

there may be less publicly available information about the financial condition of municipal security issuers than for issuers of other types of securities, making the securities more difficult to value. The price a fund could receive upon the sale of a portfolio investment may differ from the fund’s valuation of the investment, particularly for investments that trade in thin or volatile markets or that are valued using a fair valuation methodology.

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Risk [Text Block]

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Variable Rate Demand Obligations Risk: Certain variable rate demand obligations (“VRDOs”) may not have an active secondary market. These VRDOs could be difficult to dispose of if the remarketing agent defaults on its payment obligation and/or if the fund is not entitled to exercise its demand rights, which could cause a loss with respect to such VRDOs.

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Risk [Text Block]

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High Portfolio Turnover Risk: When high portfolio turnover (more than 100%) is caused by the sale of a fund’s portfolio securities and the reinvestment by the fund in other portfolio securities, such high portfolio turnover may result in increased transaction costs, including brokerage commissions, dealer mark-ups and other transaction costs. Additionally, the sale of a fund’s portfolio securities may result in the distribution of higher capital gains as compared to a fund with less active trading policies. Alternatively, for fixed income funds, a higher portfolio turnover may be in part the result of bonds being held to their maturity, which may have a minimal impact on transaction costs and taxes.

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Risk [Text Block]

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Operational Risk: Operational risks include human error, changes in personnel, system changes, faults in communication, and failures in systems, technology, or processes, and the use of artificial intelligence and machine

learning (“AI”). Various operational events or circumstances are outside a fund’s or its advisor’s control, including instances at third parties. A fund and its advisor seek to reduce these operational risks through controls and procedures. However, measures that seek to reduce these operational risks through controls and procedures may not address every possible risk and may be inadequate to address these risks.

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