Summary Prospectus      December 1, 2018 American Century Investments® Focused Dynamic Growth Fund
Investor Class: ACFOX I Class: ACFSX	R Class: ACFCX Advisor Class: ACFDX	R6 Class: ACFNX

Before you invest, you may want to review the fund’s prospectus, which contains more information about the fund and its risks. You can find the fund’s prospectus and other information about the fund online at the web addresses listed below. You can also get this information at no cost by calling or sending an email request. The fund’s prospectus and other information are also available from financial intermediaries (such as banks and broker-dealers) through which shares of the fund may be purchased or sold.
Retail Investors americancentury.com/funds/fund_reports.jsp 1-800-345-2021 or 816-531-5575 prospectus@americancentury.com	Financial Professionals americancentury.com/ipro/funds/fund_reports_mf.jsp 1-800-345-6488 advisor_prospectus@americancentury.com
This summary prospectus incorporates by reference the fund’s prospectus and statement of additional information (SAI), each dated December 1, 2018 (as supplemented at the time you receive this summary prospectus), as well as the Report of Independent Registered Public Accounting Firm and the financial statements included in the fund’s annual report to shareholders, dated July 31, 2018. The fund's SAI and annual report may be obtained, free of charge, in the same manner as the prospectus.

Investment Objective 

The fund seeks long-term capital growth. 

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

Shareholder Fees (fees paid directly from your investment)
	Investor	I	Advisor	R	R6
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	$25	None	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
	Investor	I	Advisor	R	R6
Management Fee1	1.02%	0.82%	1.02%	1.02%	0.67%
Distribution and Service (12b-1) Fees	None	None	0.25%	0.50%	None
Other Expenses	0.00%	0.00%	0.00%	0.00%	0.00%
Total Annual Fund Operating Expenses	1.02%	0.82%	1.27%	1.52%	0.67%
Fee Waver2	0.17%	0.17%	0.17%	0.17%	0.17%
Total Annual Fund Operating Expenses After Fee Waver	0.85%	0.65%	1.10%	1.35%	0.50%

¹ The management fee has been restated to reflect the decrease in the management fee schedule effective August 1, 2018.

² The advisor has agreed to waive 0.17 percentage points of the fund’s management fee. The advisor expects this waiver to continue until November 30, 2019, and cannot terminate it prior to such date without the approval of the Board of Directors.

Example

The example below is intended to help you compare the costs of investing in the fund with the costs 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 and that you earn a 5% return each year. You may be required to pay brokerage commissions on your

purchases of Investor or I Class shares of the fund, which are not reflected in the example. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be: 

	1 year	3 years	5 years	10 years
Investor Class	$87	$308	$547	$1,232
I Class	$67	$245	$439	$998
Advisor Class	$112	$387	$681	$1,518
R Class	$138	$464	$814	$1,797
R6 Class	$51	$198	$357	$819

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 29% of the average value of its portfolio.

Principal Investment Strategies 

The portfolio managers look for stocks of early and rapid stage growth companies they believe will increase in value over time. The portfolio managers make their investment decisions based primarily on their analysis of individual companies, rather than on broad economic forecasts. Management of the fund is based on the belief that, over the long term, stock price movements follow growth in earnings, revenues and/or cash flow. Under normal market conditions, the fund will invest in 30 to 45 securities.

The portfolio managers use a variety of analytical research tools and techniques to identify the stocks of companies that meet their investment criteria. Under normal market conditions, the portfolio managers seek securities of companies whose earnings or revenues are not only growing, but growing at an accelerated pace. This includes companies whose growth rates, although still negative, are less negative than prior periods, and companies whose growth rates are expected to accelerate relative to factors including recent trends, market expectations, peers and historical data. Among other variables, the portfolio managers will consider the fund’s growth and momentum profile relative to the benchmark. Other analytical techniques help identify additional signs of business improvement, such as increasing or the expectation of increasing cash flows, or other indications of financial health. These techniques help the portfolio managers buy or hold the stocks of companies they believe have favorable growth prospects and sell the stocks of companies whose characteristics no longer meet their criteria.

Although the portfolio managers intend to invest the fund’s assets primarily in U.S. securities, the fund may invest in securities of foreign companies when these securities meet the portfolio managers’ standards of selection.

The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.

Principal Risks

• Growth Stocks - Investments in growth stocks may be more volatile than other stocks and the overall stock market. These stocks are typically priced higher than other stocks because of their growth potential, which may or may not be realized. These risks may even be greater for early and rapid stage growth companies.

• Issuer Focus Risk - Under normal market conditions, the fund will invest in 30 to 45 securities. As result, the fund’s performance may be more volatile than the performance of funds holding more securities.

• Style Risk - If at any time the market is not favoring the fund’s growth investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Foreign Securities - The fund may invest in foreign securities, which can be riskier than investing in U.S. securities. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance 

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (3Q 2009): 18.48% Lowest Performance Quarter (3Q 2008): -22.37%

As of September 30, 2018, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 26.63%.

Average Annual Total Returns For the calendar year ended December 31, 2017	1 year	5 years	10 years	Since Inception	Inception Date
Investor Class Return Before Taxes	34.55%	15.96%	4.96%	—	05/31/2006
Return After Taxes on Distributions	34.55%	15.70%	4.76%	—	05/31/2006
Return After Taxes on Distributions and Sale of Fund Shares	19.56%	12.85%	3.92%	—	05/31/2006
I Class Return Before Taxes	34.83%	16.21%	5.17%	—	05/31/2006
Advisor Class Return Before Taxes	34.25%	15.68%	4.71%	—	05/31/2006
R Class Return Before Taxes	33.89%	15.39%	4.44%	—	05/31/2006
R6 Class Return Before Taxes	35.01%	—	—	32.85%	12/01/2016
Russell 1000® Growth Index   (reflects no deduction for fees, expenses or taxes)	30.21%	17.32%	9.99%	—	05/31/2006

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs. 

Portfolio Management

Investment Advisor

American Century Investment Management, Inc.

Portfolio Managers

Keith Lee, CFA, Vice President and Senior Portfolio Manager, has been a member of the team that manages the fund since 2016.

Michael Li, Vice President and Portfolio Manager, has been a member of the team that manages the fund since 2016.

Henry He, CFA, Portfolio Manager and Senior Investment Analyst, has been a member of the team that manages the fund since 2016.

Prabha Ram, CFA, Portfolio Manager and Senior Investment Analyst, has been a member of the team that manages the fund since 2016.

Purchase and Sale of Fund Shares

You may purchase or redeem shares of the fund on any business day through our website at americancentury.com, in person (at one of our Investor Centers), by mail (American Century Investments, P.O. Box 419200, Kansas City, MO 64141-6200), by telephone at 1-800-345-2021 (Investor Services Representative) or 1-800-345-3533 (Business, Not-For-Profit and Employer-Sponsored Retirement Plans), or through a financial intermediary. Shares may be purchased and redemption proceeds received by electronic bank transfer, by check or by wire. 

Unless otherwise specified below, the minimum initial investment amount to open an account is $2,500 ($2,000 for Coverdell Education Savings Accounts). Investors opening accounts through financial intermediaries may open an account with $250 for Investor, Advisor and R Classes, but the financial intermediaries may require their clients to meet different investment minimums. The minimum may be waived for broker-dealer sponsored wrap program accounts, fee based accounts, and accounts through bank/trust and wealth management advisory organizations. 

The minimum initial investment amount for I Class is generally $5 million ($3 million for endowments and foundations), but the minimum may be waived if you have an aggregate investment in the American Century family of funds of $10 million or more ($5 million for endowments and foundations). This includes accounts held directly with American Century and those held through a financial intermediary. 

There is no minimum initial investment amount for R6 Class shares.

For the Investor, Advisor, R and R6 Classes, there is no minimum initial investment amount for certain employer-sponsored retirement plans, however, financial intermediaries or plan recordkeepers may require plans to meet different minimums. For purposes of fund minimums, employer-sponsored retirement plans do not include SEP IRAs, SIMPLE IRAs or SARSEPs.  Employer-sponsored retirement plans are not eligible to invest in the I Class.

There is a $50 minimum for subsequent purchases, except that there is no subsequent purchase minimum for financial intermediaries or employer-sponsored retirement plans.

Tax Information 

Fund distributions are generally taxable as ordinary income or capital gains, unless you are investing through a tax-deferred account such as a 401(k) or individual retirement account (in which case you may be taxed upon withdrawal of your investment from such account). 

Payments to Broker-Dealers and Other Financial Intermediaries 

If you purchase the fund through a broker-dealer or other financial intermediary (such as a bank, insurance company, plan sponsor or financial professional), the fund and its related companies may pay the intermediary for the sale of fund shares and related services for investments in all classes except the R6 Class. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the fund over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

©2018 American Century Proprietary Holdings, Inc. All rights reserved.

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