Sep. 13, 2017
American Beacon Small Cap Value Fund American Beacon Balanced Fund American Beacon Large Cap Value Fund American Beacon Mid-Cap Value Fund American Beacon International Equity Fund Supplement dated September 13, 2017 to the Prospectus and Summary Prospectus dated February 28, 2017, as previously supplemented or amended In the "Fund Summaries - American Beacon Small Cap Value Fund - Principal Investment Strategies" section, the following is added following the fourth paragraph: Hotchkis and Wiley Capital Management, LLC ("Hotchkis"), another sub-advisor to the Fund, also manages two allocations of the Fund's assets, one pursuant to the fundamental research strategy discussed above and the other pursuant to a small cap diversified value strategy which seeks to exploit market inefficiencies created by irrational investor behavior ("Small Cap Diversified Value Strategy"). Hotchkis implements the Small Cap Diversified Value Strategy by using a disciplined, bottom-up investment process based on a proprietary model that is augmented by fundamental research. Hotchkis seeks broad diversified exposure to investment opportunities that are allocated to the Small Cap Diversified Value Strategy by holding approximately 300-400 portfolio securities. Hotchkis evaluates relative valuation, fundamental operating trends, deterioration of fundamentals, and the Small Cap Diversified Value Strategy's diversification guidelines, among other factors, in determining whether to sell a security.

Sep. 13, 2017

American Beacon Small Cap Value Fund

American Beacon Balanced Fund

American Beacon Large Cap Value Fund

American Beacon Mid-Cap Value Fund

American Beacon International Equity Fund

Supplement dated September 13, 2017

to the

Prospectus and Summary Prospectus dated February 28, 2017, as previously supplemented or amended

In the "Fund Summaries - American Beacon Small Cap Value Fund - Principal Investment Strategies" section, the following is added following the fourth paragraph:

Hotchkis and Wiley Capital Management, LLC ("Hotchkis"), another sub-advisor to the Fund, also manages two allocations of the Fund's assets, one pursuant to the fundamental research strategy discussed above and the other pursuant to a small cap diversified value strategy which seeks to exploit market inefficiencies created by irrational investor behavior ("Small Cap Diversified Value Strategy"). Hotchkis implements the Small Cap Diversified Value Strategy by using a disciplined, bottom-up investment process based on a proprietary model that is augmented by fundamental research. Hotchkis seeks broad diversified exposure to investment opportunities that are allocated to the Small Cap Diversified Value Strategy by holding approximately 300-400 portfolio securities. Hotchkis evaluates relative valuation, fundamental operating trends, deterioration of fundamentals, and the Small Cap Diversified Value Strategy's diversification guidelines, among other factors, in determining whether to sell a security.