
American Beacon Stephens Small Cap Growth Fund

SUMMARY PROSPECTUS April 30, 2021

As of January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Fund’s shareholder reports are no longer sent by mail, unless you speciﬁcally request paper copies of the reports from the Fund or from your ﬁnancial intermediary, such as a broker-dealer or bank. Instead, the reports are made available on a website, and you will be notiﬁed by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Fund or your ﬁnancial intermediary electronically by going to www.americanbeaconfunds.com and clicking on ‘‘Quick Links’’ and then ‘‘Register for E-Delivery.”

You may elect to receive all future reports in paper free of charge. You can inform the Fund that you wish to continue receiving paper copies of your shareholder reports by calling 1-866-345-5954, or you may directly inform your financial intermediary of your wish. A notice that will be mailed to you each time a report is posted will also include instructions for informing the Fund that you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all funds held with the American Beacon Funds Complex or your financial intermediary, as applicable.

Before you invest, you may want to review the Fund’s prospectus and statement of additional information, which contain more information about the Fund and its risks. The current prospectus and statement of additional information dated April 30, 2021, are incorporated by reference into this summary prospectus. You can find the Fund’s prospectus, statement of additional information, reports to shareholders, and other information about the Fund online at
www.americanbeaconfunds.com/resource_center/MutualFundForms.aspx. You can also get this information at no cost by calling 800-658-5811 or by sending an email request to americanbeaconfunds@ambeacon.com.

*	Formerly known as the Institutional Class.

Investment Objective

The Fund seeks long-term growth of capital.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales discounts if you and your eligible family members invest, or agree to invest in the future, at least $50,000 in all classes of the American Beacon Funds on an aggregated basis. More information about these and other discounts is available from your financial professional and in “Choosing Your Share Class” on page 45 of the Prospectus and “Additional Purchase and Sale Information for A Class Shares” on page 43 of the statement of additional information (“SAI”). With respect to purchases of shares through specific intermediaries, you may find additional information regarding sales charge discounts and waivers in Appendix A to the Fund’s Prospectus entitled “Intermediary Sales Charge Discounts, Waivers and Other Information.” Although the Fund does not impose any sales charge on Y Class shares, you may pay a commission to your broker on your purchases and sales of those shares, which is not reflected in the tables or Example below.

Shareholder Fees (fees paid directly from your investment)


Share Class	A	C	Y	R6	R5	Investor
Maximum sales charge imposed on purchases (as a percentage of offering price)	5.75 %	None	None	None	None	None
Maximum deferred sales charge (as a percentage of the lower of original offering price or redemption proceeds)	0.50 % ¹	1.00 %	None	None	None	None


Annual Fund Operating Expenses (Expenses that you pay each year as a percentage of the value of your investment)
Share Class	A	C	Y	R6	R5	Investor
Management Fees	0.93 %	0.93 %	0.93 %	0.93 %	0.93 %	0.93 %
Distribution and/or Service (12b-1) Fees	0.25 %	1.00 %	0.00 %	0.00 %	0.00 %	0.00 %
Other Expenses²	0.17 %	0.22 %	0.19 %	0.09 %	0.12 %	0.46 %
Total Annual Fund Operating Expenses	1.35 %	2.15 %	1.12 %	1.02 %	1.05 %	1.39 %
Fee Waiver and/or expense reimbursement³	(0.07 %)	(0.09 %)	(0.06 %)	(0.06 %)	(0.06 %)	(0.08 %)
Total Annual Fund Operating Expenses after fee waiver and/or expense reimbursement⁴	1.28 %	2.06 %	1.06 %	0.96 %	0.99 %	1.31 %

1	A contingent deferred sales charge (‘‘CDSC’’) of 0.50% will be charged on certain purchases of $1,000,000 or more of A Class shares that are redeemed in whole or part within 18 months of purchase.

2	Other Expenses for Y Class and Investor Class shares include 0.01% securities lending expenses.

American Beacon Advisors, Inc. (the “Manager”) has contractually agreed to waive fees and/or reimburse expenses of the Fund’s A Class, C Class, Y Class, R6 Class, R5 Class and Investor Class shares, as applicable, through April 30, 2022 to the extent that Total Annual Fund Operating Expenses exceed 1.28% for the A Class, 2.06% for the C Class, 1.05% for the Y Class, 0.96% for the R6 Class, 0.99% for the R5 Class and 1.30% for the Investor Class (excluding taxes, interest, brokerage commissions, acquired fund fees and expenses, securities lending fees, expenses associated with securities sold short, litigation, and other extraordinary expenses). The contractual expense reimbursement can be changed or terminated only in the discretion and with the approval of a majority of the Fund’s Board of Trustees (the “Board”). The Manager will itself waive fees and/or reimburse expenses of the Fund to maintain the contractual expense ratio caps for each applicable class of shares or make arrangements with other service providers to do so. The Manager may also, from time to time, voluntarily waive fees and/or reimburse expenses of the Fund. The Manager can be reimbursed by the Fund for any contractual or voluntary fee waivers

SSCG043021

American Beacon Stephens Small Cap Growth Fund - Summary Prospectus1

or expense reimbursements if reimbursement to the Manager (a) occurs within three years from the date of the Manager’s waiver/reimbursement and (b) does not cause the Total Annual Fund Operating Expenses of a class to exceed the lesser of the contractual percentage limit in effect at the time of the waiver/reimbursement or the time of the recoupment.

The Total Annual Fund Operating Expenses after fee waiver and/or expense reimbursement for the R6 Class shares do not correlate to the ratio of expenses to average net assets, net of reimbursements, provided in the Fund’s Financial Highlights table, which reflects the Fund’s expenses for the fiscal year ended December 31, 2020, including its previous fee waiver and/or expense reimbursement agreements. The Annual Fund Operating Expenses table reflects the new fee waiver and/or expense reimbursement agreement that was approved by the Fund’s Board effective through April 30, 2022, which differs from one or more agreements that were effective during the fiscal year ended December 31, 2020.

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, except that the Example reflects the fee waiver/expense reimbursement arrangement for each share class through April 30, 2022. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:


Share Class	1 Year	3 Years	5 Years	10 Years
A	$ 698	$ 972	$ 1,266	$ 2,100
C	$ 309	$ 664	$ 1,146	$ 2,476
Y	$ 108	$ 350	$ 611	$ 1,358
R6	$ 98	$ 319	$ 557	$ 1,242
R5	$ 101	$ 328	$ 574	$ 1,277
Investor	$ 133	$ 432	$ 753	$ 1,662

Assuming no redemption of shares:


Share Class	1 Year	3 Years	5 Years	10 Years
C	$ 209	$ 664	$ 1,146	$ 2,476

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 portfolio turnover rate was 18% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities of small capitalization companies. The Fund considers a company to be a small capitalization company if it has a market capitalization (stock market worth), at the time of investment, similar to the market capitalizations of the companies in the Russell 2000 Index. The capitalization range of that index is subject to change over time due to market activity or changes in the composition of the index. As of December 31, 2020, the market capitalizations of the companies in the Russell 2000 Index ranged from $2 million to $15.5 billion.

Most of the assets of the Fund are invested in U.S. common stocks the sub-advisor, Stephens Investment Management Group, LLC (“SIMG”), believes have clear indicators of future earnings growth, or that demonstrate other potential for growth of capital. The Fund may invest in other securities, including master limited partnerships (“MLPs”), real estate investment trusts (“REITs”), American Depositary Receipts (“ADRs”) and U.S. dollar denominated foreign stock traded on U.S. exchanges. In selecting companies for the Fund, SIMG employs quantitative analysis and fundamental research with a focus on earnings growth. SIMG will sell a security when appropriate and consistent with the Fund’s investment objectives and policies.

Although the Fund seeks investments across a number of sectors, from time to time, based on portfolio positioning to reflect its benchmark index, the Fund may have significant positions in particular sectors, including the Information Technology sector. However, as the sector composition of the Fund’s portfolio changes over time, the Fund’s exposure to the Information Technology sector may be lower at a future date, and the Fund’s exposure to other market sectors may be higher.

The Fund may also invest cash balances in other investment companies, including money market funds, and may lend its securities to broker-dealers and other institutions to earn additional income.

Principal Risks

There is no assurance that the Fund will achieve its investment objective and you could lose part or all of your investment in the Fund. The Fund is not designed for investors who need an assured level of current income and is intended to be a long-term investment. The Fund is not a complete investment program and may not be appropriate for all investors. Investors should carefully consider their own investment goals and risk tolerance before investing in the Fund. The principal risks of investing in the Fund listed below are presented in alphabetical order and not in order of importance or potential exposure. Among other matters, this presentation is intended to facilitate your ability to find particular risks and compare them with the risks of other funds. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears.

Cybersecurity and Operational Risk
Operational risks arising from, among other problems, human errors, systems and technology disruptions or failures, or cybersecurity incidents may negatively impact the Fund and its service providers as well as the ability of shareholders to transact with the Fund. Cybersecurity incidents may allow an unauthorized party to gain access to Fund assets, shareholder data, or proprietary information, or cause the Fund or its service providers, as well as securities trading venues and their service providers, to suffer data corruption or lose operational functionality. It is not possible for the Fund or its service providers to identify all of the operational risks that may affect the Fund or to develop processes and controls to completely eliminate or mitigate their occurrence or effects. Most issuers in which the Fund invests are heavily dependent on computers for data storage and operations, and require ready access to the internet to conduct their business. Thus, cybersecurity incidents could also affect issuers of securities in which the Fund invests, leading to significant loss of value.

Equity Investments Risk
Equity securities are subject to investment risk and market risk. The Fund may invest in the following equity securities, which may expose the Fund to the following additional risks:

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Common Stock Risk. The value of a company’s common stock may fall as a result of factors affecting the company, companies in the same industry or sector, or the financial markets overall. Common stock generally is subordinate to preferred stock upon the liquidation or bankruptcy of the issuing company.

2American Beacon Stephens Small Cap Growth Fund - Summary Prospectus

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Depositary Receipts and U.S. Dollar-Denominated Foreign Stocks Traded on U.S. Exchanges Risk. Depositary receipts and U.S. dollar-denominated foreign stocks traded on U.S. exchanges are subject to certain of the risks associated with investing directly in foreign securities, including, but not limited to, currency exchange rate fluctuations, political and financial instability in the home country of a particular depositary receipt or foreign stock, less liquidity, more volatility, less government regulation and supervision and delays in transaction settlement.

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Master Limited Partnerships (“MLPs”) Risk. Investing in MLPs involves certain risks related to investing in the underlying assets of the MLPs and risks associated with pooled investment vehicles. Investments held by MLPs may be relatively illiquid, limiting the MLPs’ ability to change their portfolios promptly in response to changes in economic or other conditions. MLPs may have limited financial resources, their securities may trade infrequently and in limited volume, they may be difficult to value, and they may be subject to more abrupt or erratic price movements than securities of larger or more broadly based companies. Holders of units in MLPs have more limited rights to vote on matters affecting the partnership and may be required to sell their common units at an undesirable time or price. The Fund’s investments in MLPs will be limited to no more than 25% of its assets in order for the Fund to meet the requirements necessary to qualify as a “regulated investment company” under the Internal Revenue Code of 1986, as amended (“Internal Revenue Code”).

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Real Estate Investment Trusts (“REITs”) Risk. Investments in REITs are subject to the risks associated with investing in the real estate industry, including, among other risks: adverse developments affecting the real estate industry; declines in real property values; changes in interest rates; defaults by mortgagors or other borrowers and tenants; lack of availability of mortgage funds or financing; extended vacancies of properties, especially during economic downturns; casualty or condemnation losses; and governmental actions, such as changes to tax laws, zoning regulations or environmental regulations. REITs also are dependent upon the skills of their managers and are subject to heavy cash flow dependency or self-liquidation. Regardless of where a REIT is organized or traded, its performance may be affected significantly by events in the region where its properties are located. Domestic REITs could be adversely affected by failure to qualify for tax-free “pass-through” of distributed net income and net realized gains under the Internal Revenue Code of 1986, as amended (“Internal Revenue Code”), or to maintain their exemption from registration under the Investment Company Act of 1940, as amended (“Investment Company Act”). REITs typically incur fees that are separate from those incurred by the Fund. Accordingly, the Fund’s investment in REITs will result in the layering of expenses such that shareholders will indirectly bear a proportionate share of the REITs’ operating expenses, in addition to paying Fund expenses. The value of REIT common stock may decline when interest rates rise. REITs tend to be small- to mid-capitalization securities and, as such, are subject to the risks of investing in small- to mid-capitalization securities.

Foreign Investing Risk
Non-U.S. investments carry potential risks not associated with U.S. investments. Such risks include, but are not limited to: (1) currency exchange rate fluctuations, (2) political and financial instability, (3) less liquidity, (4) lack of uniform accounting, auditing and financial reporting standards, (5) greater volatility, (6) different government regulation and supervision of foreign stock exchanges, brokers and listed companies, and (7) delays in transaction settlement in some foreign markets. The Fund’s investment in a foreign issuer may subject the Fund to regulatory, political, currency, security, economic and other risks associated with that country. Global economic and financial markets are becoming increasingly interconnected and conditions (including recent volatility and instability) and events (including natural disasters) in one country, region or financial market may adversely impact issuers in a different country, region or financial market.

Growth Companies Risk
Growth companies are expected to increase their earnings at a certain rate. When these expectations are not met, the prices of these stocks may decline, even if earnings showed an absolute increase. The Fund’s investments in growth companies may be more sensitive to company earnings and more volatile than the market in general primarily because their stock prices are based heavily on future expectations. If the sub-advisor’s assessment of the prospects for a company’s growth is incorrect, then the price of the company’s stock may fall or not approach the value that the sub-advisor has placed on it. Growth company stocks may also lack the dividend yield that can cushion stock price declines in market downturns.

Investment Risk
An investment in the Fund is not a deposit with a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. When you sell your shares of the Fund, they could be worth less than what you paid for them. Therefore, you may lose money by investing in the Fund.

Issuer Risk
The value of, and/or the return generated by, a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets.

Market Risk
The Fund is subject to the risk that the securities markets will move down, sometimes rapidly and unpredictably, based on overall economic conditions and other factors, which may negatively affect the Fund’s performance. Equity securities generally have greater price volatility than fixed income securities, although under certain market conditions fixed income securities may have comparable or greater price volatility. During a general downturn in the securities markets, multiple assets may decline in value simultaneously. Prices in many financial markets have increased significantly over the last decade, but there have also been periods of adverse market and financial developments and cyclical change during that timeframe, which have resulted in unusually high levels of volatility in domestic and foreign financial markets that has caused losses for investors and may occur again in the future. The value of a security may decline due to adverse issuer-specific conditions, general market conditions unrelated to a particular issuer, or factors that affect a particular industry or industries. Changes in the financial condition of a single issuer or market segment also can impact the market as a whole. Geopolitical and other events, including war, terrorism, economic uncertainty, trade disputes, pandemics, public health crises, natural disasters and related events have led, and in the future may continue to lead, to instability in world economies and markets generally and reduced liquidity in equity, credit and fixed-income markets, which may disrupt economies and markets and adversely affect the value of your investment. Changes in value may be temporary or may last for extended periods. Policy changes by the U.S. government and/or Federal Reserve and political events within the U.S. and abroad, including changes in the U.S. presidential administration and Congress, may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Markets and market participants are increasingly reliant upon both publicly available and proprietary information data systems. Data imprecision, software or other technology malfunctions, programming inaccuracies, unauthorized use or access, and similar circumstances may impair the performance of these systems and may have an adverse impact upon a single issuer, a group of issuers, or the market at large. The financial markets generally move in cycles, with periods of rising prices followed by periods of declining prices. The value of your investment may reflect these fluctuations.

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Recent Market Events. An outbreak of infectious respiratory illness caused by a novel coronavirus, known as COVID-19, was first detected in December 2019 and has subsequently spread globally. The transmission of COVID-19 and efforts to contain its spread have resulted, and may continue to result, in significant disruptions to business operations, widespread business closures and layoffs, travel restrictions and closed borders, prolonged quarantines and stay-at-home orders, disruption of and delays in healthcare service preparation and delivery, service and event changes, and lower consumer demand, as well as general concern and uncertainty that has negatively affected the global economy. The impact of the COVID-19 pandemic may last for an extended period of time and may result in a sustained economic downturn or recession. The U.S. Federal Reserve and the U.S. federal government have taken numerous measures to address the economic impact of the COVID-19 pandemic and stimulate the U.S. economy. The ultimate effects of these and other efforts that may be taken may not be known for some time.

The Federal Reserve has spent hundreds of billions of dollars to keep credit flowing through short-term money markets and has signaled that it plans to maintain its interventions at an elevated level. Amid these ongoing efforts, concerns about the markets’ dependence on the Federal Reserve’s provision of

American Beacon Stephens Small Cap Growth Fund - Summary Prospectus3

liquidity have grown. Future legislative, regulatory and policy changes may result in more restrictions on international trade, less stringent prudential regulation of certain players in the financial markets, and significant new investments in infrastructure and national defense. High public debt in the U.S. and other countries creates ongoing systemic and market risks and policymaking uncertainty. A rise in protectionist trade policies, slowing global economic growth, risks associated with the United Kingdom’s departure from the European Union on December 31, 2020, commonly referred to as “Brexit,” and a trade agreement between the United Kingdom and the European Union, the risks associated with ongoing trade negotiations with China, the possibility of changes to some international trade agreements, tensions or open conflict between nations, or political or economic dysfunction within some nations that are major producers of oil could affect the economies of many nations, including the United States, in ways that cannot necessarily be foreseen at the present time.

Economists and others have expressed increasing concern about the potential effects of global climate change on property and security values. Certain issuers, industries and regions may be adversely affected by the impacts of climate change, including on the demand for and the development of goods and services and related production costs, and the impacts of legislation, regulation and international accords related to climate change, as well as any indirect consequences of regulation or business trends driven by climate change.

Mid-Capitalization Companies Risk
Investing in the securities of mid-capitalization companies involves greater risk and the possibility of greater price volatility than investing in larger-capitalization and more established companies. Since mid-capitalization companies may have narrower commercial markets and more limited operating history, product lines, and managerial and financial resources than larger, more established companies, the securities of these companies may lack sufficient market liquidity, and they can be particularly sensitive to expected changes in interest rates, borrowing costs and earnings.

Other Investment Companies Risk
To the extent that the Fund invests in shares of other registered investment companies, the Fund will indirectly bear the fees and expenses charged by those investment companies in addition to the Fund’s direct fees and expenses. To the extent the Fund invests in other investment companies that invest in equity securities, fixed income securities and/or foreign securities, or that track an index, the Fund is subject to the risks associated with the underlying investments held by the investment company or the index fluctuations to which the investment company is subject. The Fund will be subject to the risks associated with investments in those companies, including but not limited to the following:

■	Money Market Funds. Investments in money market funds are subject to interest rate risk, credit risk, and market risk.

Redemption Risk
The Fund may experience periods of high levels of redemptions that could cause the Fund to sell assets at inopportune times or at a loss or depressed value. The sale of assets to meet redemption requests may create net capital gains, which could cause the Fund to have to distribute substantial capital gains. Redemption risk is heightened during periods of declining or illiquid markets. During periods of heavy redemptions, the Fund may borrow funds through the interfund credit facility or from a bank line of credit, which may increase costs. Heavy redemptions could hurt the Fund’s performance.

Sector Risk
When the Fund focuses its investments in certain sectors of the economy, its performance may be driven largely by sector performance and could fluctuate more widely than if the Fund were invested more evenly across sectors. Individual sectors may be more volatile, and may perform differently, than the broader market. As the Fund’s portfolio changes over time, the Fund’s exposure to a particular sector may become higher or lower.

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Information Technology Sector Risk. The information technology sector includes companies engaged in internet software and services, technology hardware and storage peripherals, electronic equipment and components, and semiconductors and semiconductor equipment. Information technology companies face intense competition, both domestically and internationally, which may have an adverse effect on profit margins. Information technology companies may have limited product lines, markets, financial resources or personnel. The products of information technology companies may face rapid product obsolescence due to technological developments and frequent new product introduction, unpredictable changes in growth rates and competition for the services of qualified personnel. Failure to introduce new products, develop and maintain a loyal customer base or achieve general market acceptance for their products could have a material adverse effect on a company’s business. Companies in the information technology sector are heavily dependent on intellectual property and the loss of patent, copyright or trademark protections may adversely affect the profitability of these companies.

Securities Lending Risk
To the extent the Fund lends its securities, it may be subject to the following risks: i) the securities in which the Fund reinvests cash collateral may decrease in value, causing the Fund to incur a loss, or may not perform sufficiently to cover the Fund’s payment to the borrower of a pre-negotiated fee or “rebate” for the use of that cash collateral in connection with the loan; ii) non-cash collateral may decline in value, resulting in the Fund becoming under-secured; iii) delays may occur in the recovery of loaned securities from borrowers, which could result in the Fund being unable to vote proxies or settle transactions or cause the Fund to incur increased costs; and iv) if the borrower becomes subject to insolvency or similar proceedings, the Fund could incur delays in its ability to enforce its rights in its collateral.

Securities Selection Risk
Securities selected by the sub-advisor for the Fund may not perform to expectations. This could result in the Fund’s underperformance compared to its benchmark index(es), or other funds with similar investment objectives or strategies.

Small-Capitalization Companies Risk
Investing in the securities of small-capitalization companies involves greater risk and the possibility of greater price volatility than investing in larger-capitalization and more established companies. Since small-capitalization companies may have narrower commercial markets, and more limited operating history, product lines, and managerial and financial resources than larger, more established companies, the securities of these companies may lack sufficient market liquidity and they can be particularly sensitive to changes in interest rates, borrowing costs and earnings.

Fund Performance

The bar chart and table below provide an indication of risk by showing changes in the Fund’s performance over time. The bar chart shows how the Fund’s performance has varied from year to year. The table shows how the Fund’s average annual total returns compare to a broad-based market index, which is the Fund’s benchmark index, for the periods indicated.

On February 24, 2012, the Fund acquired all the assets and assumed all the liabilities of the Fund’s predecessor. In connection with that reorganization, the Investor Class and R5 Class shares of the Fund adopted the performance history, without the deduction of the maximum applicable sales charge, and financial statements of the Class A and Class I shares, respectively, of the Fund’s predecessor. In the bar chart and table below, the performance of the Fund’s Investor Class shares for periods prior to February 24, 2012 is the performance of the Class A shares of the Fund’s predecessor. The table below also shows the performance of the A Class, C Class, Y Class, R5 Class, and R6 Class shares of the Fund. In the table below, the performance shown for the R5 Class shares of the Fund for periods prior to February 24, 2012 is the performance of the Class I shares of the Fund’s predecessor. The performance shown for the Fund’s Y Class, A Class and C Class shares for periods prior to February 24, 2012 represents the returns achieved by the Class A shares of the Fund’s predecessor. In the table below, the performance for the Fund’s R6 Class shares for periods prior to April 30, 2019 represents the returns achieved by the Class I shares of the Fund’s predecessor from January 1, 2011 through February 23, 2012, and the performance of the Fund’s Investor Class shares from February 24, 2012 through April 29,

4American Beacon Stephens Small Cap Growth Fund - Summary Prospectus

2019. In each case, the newer share classes would have had similar annual returns to the older share classes because the shares of each class represent investments in the same portfolio securities. However, the older share classes had different expenses than the newer share classes, which would affect performance. The performance of the newer share classes shown in the bar chart and table has not been adjusted for differences in operating expenses between those share classes and the older share classes, but the A Class and C Class shares performance has been adjusted for the impact of the maximum applicable sales charge. You may obtain updated performance information on the Fund’s website at www.americanbeaconfunds.com. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Calendar year total returns for Investor Class Shares. Year Ended 12/31

Highest Quarterly Return:
37.56% 2nd Quarter 2020
01/01/2011 through 12/31/2020

Lowest Quarterly Return:
-22.26% 1st Quarter 2020
01/01/2011 through 12/31/2020

Average annual total returns for periods ended December 31, 2020


	Inception Date of Class	1 Year	5 Years	10 Years
Investor Class	12/01/2005
Returns Before Taxes		37.18 %	17.75 %	13.30 %
Returns After Taxes on Distributions		33.86 %	14.53 %	11.14 %
Returns After Taxes on Distributions and Sales of Fund Shares		24.41 %	13.58 %	10.51 %


	Inception Date of Class	1 Year	5 Years	10 Years
Share Class (Before Taxes)
A	02/24/2012	29.38 %	16.33 %	12.54 %
C	02/24/2012	35.16 %	16.81 %	12.45 %
Y	02/24/2012	37.56 %	18.01 %	13.51 %
R5	08/31/2006	37.56 %	18.07 %	13.61 %
R6	04/30/2019	37.76 %	18.11 %	13.62 %


	1 Year	5 Years	10 Years
Index (Reflects no deduction for fees, expenses or taxes)
Russell 2000^® Growth Index	34.63 %	16.36 %	13.48 %

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 income taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The return after taxes on distributions and sale of Fund shares may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Fund shares at the end of the measurement period. If you are a tax-exempt entity or hold your Fund shares through a tax-deferred arrangement, such as an individual retirement account (“IRA”) or a 401(k) plan, the after-tax returns do not apply to your situation. After-tax returns are shown only for Investor Class shares of the Fund; after-tax returns for other share classes will vary.

Management

The Manager
The Fund has retained American Beacon Advisors, Inc. to serve as its Manager.

Sub-Advisor

The Fund’s investment sub-advisor is Stephens Investment Management Group, LLC.

Portfolio Managers

Stephens Investment Management Group, LLC

Ryan E. Crane
Chief Investment Officer
Since Fund Inception (2005)^**

Kelly Ranucci
Senior Portfolio Manager
Since 2011*

John Keller
Portfolio Manager
Since 2019

John M. Thornton
Senior Portfolio Manager
Since Fund Inception (2005)**

Samuel M. Chase III
Senior Portfolio Manager
Since 2011*

*	Includes Predecessor Fund.

**	Predecessor Fund inception date.

American Beacon Stephens Small Cap Growth Fund - Summary Prospectus5

Purchase and Sale of Fund Shares

You may buy or sell shares of the Fund through a retirement plan, an investment professional, a broker-dealer, or other financial intermediary. You may purchase or redeem shares of the Fund on any day the New York Stock Exchange (“NYSE”) is open, at the Fund’s net asset value (“NAV”) per share next calculated after your order is received in proper form, subject to any applicable sales charge. The Manager may, in its sole discretion, allow certain individuals to invest directly in the Fund. For more information regarding eligibility to invest directly please see “About Your Investment - Purchase and Redemption of Shares.” Direct mutual fund account shareholders may buy subsequent shares or sell shares in various ways:


Internet	www.americanbeaconfunds.com
Phone	To reach an American Beacon representative call 1-800-658-5811, option 1 Through the Automated Voice Response Service call 1-800-658-5811, option 2 (Investor Class only)
Mail	American Beacon Funds P.O. Box 219643 Kansas City, MO 64121-9643	Overnight Delivery: American Beacon Funds c/o DST Asset Manager Solutions, Inc. 330 West 9th Street Kansas City, MO 64105


	New Account	Existing Account
Share Class	Minimum Initial Investment Amount	Purchase/Redemption Minimum by Check/ACH/Exchange	Purchase/Redemption Minimum by Wire
C	$1,000	$50	$250
A, Investor	$2,500	$50	$250
Y	$100,000	$50	None
R5	$250,000	$50	None
R6	None	$50	None

Tax Information

Dividends, capital gains distributions, and other distributions, if any, that you receive from the Fund are subject to federal income tax and may also be subject to state and local income taxes, unless you are a tax-exempt entity or your account is tax-deferred, such as an individual retirement account or a 401(k) plan (in which case you may be taxed later, upon the withdrawal of your investment from such account or plan).

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and the Fund’s distributor, Resolute Investment Distributors, Inc., or the Manager may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your individual financial professional to recommend the Fund over another investment. Ask your individual financial professional or visit your financial intermediary’s website for more information.

6American Beacon Stephens Small Cap Growth Fund - Summary Prospectus