
American Beacon Stephens Mid-Cap Growth Fund^SM

SUMMARY PROSPECTUS May 1, 2022

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 May 1, 2022, 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.

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 41 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.”

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	0.80 %	0.80 %	0.80 %	0.80 %	0.80 %	0.80 %
Distribution and/or Service (12b-1) Fees	0.25 %	1.00 %	0.00 %	0.00 %	0.00 %	0.00 %
Other Expenses²	0.09 %	0.18 %	0.17 %	0.08 %	0.10 %	0.34 %
Total Annual Fund Operating Expenses	1.14 %	1.98 %	0.97 %	0.88 %	0.90 %	1.14 %
Fee Waiver and/or expense reimbursement³	(0.00 %)	(0.04 %)	(0.02 %)	(0.00 %)	(0.01 %)	(0.00 %)
Total Annual Fund Operating Expenses after fee waiver and/or expense reimbursement	1.14 %	1.94 %	0.95 %	0.88 %	0.89 %	1.14 %

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.

During the fiscal year ended December 31, 2021, the Fund paid amounts to American Beacon Advisors, Inc. (the “Manager”) that were previously waived and/or reimbursed under a contractual fee waiver/expense reimbursement for the Fund’s A Class, C Class, R6 Class, and R5 Class shares in the amount of 0.02% for the A Class, 0.02% for the C Class, 0.01% for the R6 Class, and 0.01% for the R5 Class.

The Manager has contractually agreed to waive fees and/or reimburse expenses of the Fund’s C Class, Y Class, and R5 Class shares, as applicable, through April 30, 2023 to the extent that Total Annual Fund Operating Expenses exceed 1.94% for the C Class, 0.95% for the Y Class, and 0.89% for the R5 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 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.

SMCG050122

American Beacon Stephens Mid-Cap Growth Fund - Summary Prospectus1

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 this Example reflects the fee waiver/expense reimbursement arrangement for the C Class, Y Class and R5 Class shares through April 30, 2023. 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	$685	$916	$1,167	$1,881
C	$297	$618	$1,064	$2,303
Y	$97	$307	$534	$1,188
R6	$90	$281	$488	$1,084
R5	$91	$286	$497	$1,107
Investor	$116	$362	$628	$1,386

Assuming no redemption of shares:


Share Class	1 Year	3 Years	5 Years	10 Years
C	$197	$618	$1,064	$2,303

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 28% 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 medium capitalization companies. The Fund considers a company to be a medium capitalization company if it has a market capitalization (stock market worth), at the time of investment, between $1 billion and the market capitalization of the largest company in the Russell Midcap^® Index, which was $58.4 billion as of February 28, 2022. The Fund may also invest in equity securities of small-capitalization and large-capitalization companies.

Most of the assets of the Fund are invested in U.S. common stocks that 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 U.S. dollar denominated foreign stock traded on U.S. exchanges, American Depositary Receipts (“ADRs”), master limited partnerships (“MLPs”), and real estate investment trusts (“REITs”). In selecting companies for the Fund, SIMG primarily employs fundamental research with a focus on earnings growth. SIMG will sell a security when appropriate and consistent with the Fund’s investment objective 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 government money market funds. The Fund may seek to earn additional income by lending its securities to certain qualified broker-dealers and institutions.

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:

■

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.

■

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.

■

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

2American Beacon Stephens Mid-Cap Growth Fund - Summary Prospectus

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”).

■

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) increased 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 or decrease, the prices of these stocks may decline, sometimes sharply, 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 an 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 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.

Large-Capitalization Companies Risk
The securities of large market capitalization companies may underperform other segments of the market because such companies may be less responsive to competitive challenges and opportunities and, at times, such companies may be out of favor with investors. Many larger-capitalization companies also may be unable to attain the high growth rates of successful smaller companies, especially during periods of economic expansion.

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, such as changes in interest or inflation rates, 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, such as changes in the U.S. presidential administration and Congress, the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, the threat of a federal government shutdown and threats not to increase the federal government’s debt limit, 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.

■

Recent Market Events Risk. An outbreak of infectious respiratory illness caused by a novel coronavirus, known as COVID-19, was first detected in late 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 pandemic has negatively affected and may continue to affect the economies of many nations, individual companies and the global securities and commodities markets, including their liquidity, in ways that cannot necessarily be foreseen at the present time. The pandemic has accelerated trends toward working remotely and shopping on-line, which may negatively affect the value of office and commercial real estate and companies that have been slow to transition to an on-line business model and has disrupted the supply chains that many

American Beacon Stephens Mid-Cap Growth Fund - Summary Prospectus3

businesses depend on. The travel, hospitality and public transit industries may suffer long-term negative effects from the pandemic and resulting changes to public behavior. Both U.S. and international markets have experienced significant volatility in recent months and years. As a result of such volatility, investment returns may fluctuate significantly. Moreover, the risks discussed herein associated with an investment in the Fund may be increased.

The Federal Reserve has spent hundreds of billions of dollars to keep credit flowing through the economy. However, the Federal Reserve recently began to reduce its interventions as the economy improved and inflation accelerated. Concerns about the markets’ dependence on the Federal Reserve’s provision of liquidity have grown as a result. High public debt in the U.S. and other countries creates ongoing systemic and market risks and policymaking uncertainty, and there may be a further increase in public debt due to the economic effects of the COVID-19 pandemic and ensuing economic relief and public health measures. Governments’ efforts to limit potential negative economic effects of the pandemic may be altered, delayed, or eliminated at inopportune times for political, policy or other reasons.

Interest rates have been unusually low in recent years in the U.S. and abroad, and central banks reduced rates further in an effort to combat the economic effects of the COVID-19 pandemic. Because there is little precedent for this situation, it is difficult to predict the impact on various markets of a significant rate increase or other significant policy changes. The U.S. Federal Reserve has started to raise interest rates, in part to address an increase in the annual inflation rate in the U.S. Over the longer term, rising interest rates may present a greater risk than has historically been the case due to the current period of relatively low rates and the effect of government fiscal and monetary policy initiatives and potential market reaction to those initiatives or their alteration or cessation.

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, war, or open conflict between nations, such as between Russia and Ukraine, 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. Russia’s military invasion of Ukraine beginning in February 2022, the responses and sanctions by the United States and other countries, and the potential for wider conflict have had, and could continue to have, severe adverse effects on regional and global economies and could further increase volatility and uncertainty in the financial markets.

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, which at times can be rapid and unpredictable, 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 changes in overall economic conditions, 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:

■	Government Money Market Funds Risk. Investments in government 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 greater to the extent that one or more investors or intermediaries control a large percentage of investments in the Fund. In addition, 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.

■

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. The market prices of information technology-related securities tend to exhibit a greater degree of market risk and sharp price fluctuations than other types of securities. These securities may fall in and out of favor with investors rapidly, which may cause sudden selling and dramatically lower market prices.

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 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.

4American Beacon Stephens Mid-Cap Growth Fund - Summary Prospectus

Small-Capitalization Companies Risk
Investing in the securities of small-capitalization companies involves greater risk and the possibility of greater price volatility, which at times can be rapid and unpredictable, 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 overall economic conditions, 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.

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. In the table below, the performance for the Fund’s A Class, C Class and Y 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 December 31, 2018 represents the returns achieved by the Class I shares of the Fund’s predecessor from January 1, 2012 through February 23, 2012, and the performance of the Fund’s R5 Class shares from February 24, 2012 through December 30, 2018. 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:
34.11% 2nd Quarter 2020
01/01/2012 through 12/31/2021

Lowest Quarterly Return:
-18.26% 1st Quarter 2020
01/01/2012 through 12/31/2021

Average annual total returns for periods ended December 31, 2021


	Inception Date of Class	1 Year	5 Years	10 Years
Investor Class	02/01/2006
Returns Before Taxes		12.20 %	21.84 %	15.99 %
Returns After Taxes on Distributions		10.31 %	20.34 %	14.66 %
Returns After Taxes on Distributions and Sales of Fund Shares		8.53 %	17.52 %	13.08 %


	Inception Date of Class	1 Year	5 Years	10 Years
Share Class (Before Taxes)
A	02/24/2012	5.71 %	20.37 %	15.25 %
C	02/24/2012	10.29 %	20.90 %	15.10 %
Y	02/24/2012	12.41 %	22.12 %	16.29 %
R6	12/31/2018	12.47 %	22.25 %	16.40 %
R5	08/31/2006	12.46 %	22.23 %	16.39 %


	1 Year	5 Years	10 Years
Index (Reflects no deduction for fees, expenses or taxes)
Russell Midcap^® Growth Index	12.73 %	19.83 %	16.63 %

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.

American Beacon Stephens Mid-Cap Growth Fund - Summary Prospectus5

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 (2006)*

Kelly Ranucci
Senior Portfolio Manager
Since 2011**

John M. Thornton
Senior Portfolio Manager
Since Fund Inception (2006)*

Samuel M. Chase III
Senior Portfolio Manager
Since 2011**

John Keller
Portfolio Manager
Since January 2019

*	Predecessor Fund inception date.

**	Includes Predecessor Fund.

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
R6	None	$50	None
R5	$250,000	$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 (“IRA”) 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 Mid-Cap Growth Fund - Summary Prospectus