SUMMARY PROSPECTUS    October 30, 2015

AB Concentrated International Growth Portfolio

Ticker: Class A–CIAGX; Class C–CICGX; Advisor Class–CIGYX

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. The Fund's Prospectus and Statement of Additional Information ("SAI"), both dated October 30, 2015, are incorporated by reference into this Summary Prospectus. For free paper or electronic copies of the Fund's Prospectus and other information about the Fund, go to http://www.ABglobal.com/links/mf, email a request to prorequest@ABglobal.com, call (800) 227-4618, or ask any financial advisor, bank, or broker-dealer who offers shares of the Fund.

INVESTMENT OBJECTIVE

The Fund's investment objective is to seek 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 and hold shares of the Fund. You may qualify for sales charge reductions if you and members of your family invest, or agree to invest in the future, at least $100,000 in AB Mutual Funds. More information about these and other discounts is available from your financial intermediary and in Investing in the Fund—Sales Charge Reduction Programs for Class A Shares on page 17 of the Fund's Prospectus and in Purchase of Shares—Sales Charge Reduction Programs on page 67 of the Fund's SAI.

Shareholder Fees (fees paid directly from your investment)

	Class A Shares	Class C Shares	Advisor Class Shares
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	4.25%	None	None
Maximum Deferred Sales Charge (Load) (as a percentage of offering price or redemption proceeds, whichever is lower)	None(a)	1.00%(b)	None
Exchange Fee	None	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

 

	Class A			Class C			Advisor Class
Management Fees		.85	%		.85	%		.85	%
Distribution and/or Service (12b-1) Fees		.25	%		1.00	%	None
Other Expenses:
Transfer Agent		.00	%(c)		.00	%(c)		.00	%(c)
Other Expenses		16.91	%		16.88	%		16.90	%
Total Other Expenses		16.91	%		16.88	%		16.90	%
Total Annual Fund Operating Expenses		18.01	%		18.73	%		17.75	%
Fee Waiver and/or Expense Reimbursement(d)		(16.71	)%		(16.68	)%		(16.70	)%
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement		1.30	%		2.05	%		1.05	%

(a)	Purchases of Class A shares in amounts of $1,000,000 or more, or by certain group retirement plans, may be subject to a 1%, 1-year contingent deferred sales charge, or CDSC, which may be subject to waiver in certain circumstances.
(b)	For Class C shares, the CDSC is 0% after the first year.
(c)	Less than .01%.

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(d) The Adviser has contractually agreed to waive its management fees and/or to bear expenses of the Fund through  October 31, 2016 to the extent necessary to prevent total Fund operating expenses (excluding acquired fund fees and expenses other than the advisory fees of any AB Mutual Funds in which the Fund may invest, interest expense, taxes, extraordinary expenses, and brokerage commissions and other transaction costs), on an annualized basis, from exceeding 1.30%, 2.05% and 1.05% of average daily net assets, respectively, for Class A, Class C and Advisor Class shares ("expense limitations"). Any fees waived and expenses borne by the Adviser may be reimbursed by the Fund until the end of the third fiscal year after the fiscal period in which the fee was waived or the expense was borne, provided that no reimbursement payment will be made that would cause the Fund's Total Annual Fund Operating Expenses to exceed the expense limitations.  

Example

The Examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Examples assume that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of these periods. The Examples also assume that your investment has a 5% return each year, that the Fund's operating expenses stay the same and that the fee waiver is in effect for only the first year. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	Class A		Class C			Advisor Class
After 1 Year	$	552	$	308	*	$	107
After 3 Years	$	3,678	$	3,553		$	3,342

* If you did not redeem your shares at the end of the period, your expenses would be decreased by approximately $100.

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys or 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 transaction costs, which are not reflected in the Annual Fund Operating Expenses or in the Examples, affect the Fund's performance. During the most recent fiscal period, the Fund's portfolio turnover rate was 2% of the average value of its portfolio.

PRINCIPAL STRATEGIES

The Adviser seeks to achieve the Fund's investment objective by investing, under normal circumstances, primarily in common stocks of non-U.S. companies, and in companies in at least three countries other than the United States.

The Fund will invest in companies that are determined by the Adviser to offer favorable long-term growth potential and that are trading at attractive valuations. The Adviser will employ an appraisal method which attempts to measure each prospective company's quality and growth rate by numerous factors. Such factors will include: a company's record and projections of profit and earnings growth, accuracy and availability of information with respect to the company, success and experience of management, accessibility of management to the Adviser, product lines and competitive position both in the United States and abroad, lack of cyclicality, large market capitalization and liquidity of the company's securities. The Adviser will compare these results to the characteristics of the general stock markets to determine the relative attractiveness of each company at a given time. The Adviser will weigh economic, political and market factors in making investment decisions; this appraisal technique attempts to measure each investment candidate not only against other stocks of the same industry and region, but also against a broad spectrum of investments.

The Fund will invest in a relatively small number of individual stocks, generally 25 to 35 companies. In addition, the Fund is a non-diversified Fund as that term is defined in the Investment Company Act of 1940 (the "1940 Act"), which means that it may invest more of its assets in a smaller number of companies than a diversified fund. The Portfolio will primarily invest in mid- and large-capitalization companies, which are currently defined for the Fund as companies that have market capitalizations of $2.0 billion or more. The Fund's holdings of non-U.S. companies may include some companies located in emerging markets, and at times emerging market companies may make up a significant portion of the Fund.

Fluctuations in currency exchange rates can have a dramatic impact of the returns of equity securities. While the Adviser may hedge the foreign currency exposure resulting from the Fund's security positions through the use of currency-related derivatives, it is not required to do so.

PRINCIPAL RISKS

• Market Risk: The value of the Fund's assets will fluctuate as the stock or bond market fluctuates. The value of its investments may decline, sometimes rapidly and unpredictably, simply because of economic changes or other events that affect large portions of the market. It includes the risk that a particular style of investing, such as the Fund's growth approach, may underperform the market generally.

• Foreign (Non-U.S.) Risk: Investments in securities of non-U.S. issuers may involve more risk than those of U.S. issuers. These securities may fluctuate more widely in price and may be less liquid due to adverse market, economic, political, regulatory or other factors. These risks may be heightened with respect to investments in emerging market countries, where there may be an increased amount of economic, political and social instability.

• Emerging Market Risk: Investments in emerging market countries may have more risk because the markets are less developed and less liquid as well as being subject to increased economic, political, regulatory or other uncertainties.

• Currency Risk: Fluctuations in currency exchange rates may negatively affect the value of the Fund's investments or reduce its returns.

• Focused Portfolio/Non-Diversification Risk: Investing in a limited number of companies, or investing more of the Fund's assets in a smaller number of companies, may have more risk because changes in the value of a single security may have a more significant effect, either negative or positive, on the Fund's net asset value, or NAV.

• Capitalization Risk: Investments in mid-capitalization companies may be more volatile than investments in large-capitalization companies. Investments in mid-capitalization companies may have additional risks because these companies have limited product lines, markets or financial resources.

• Management Risk: The Fund is subject to management risk because it is an actively-managed investment fund. The Adviser will apply its investment techniques and risk analyses in making investment decisions for the Fund, but there is no guarantee that its techniques will produce the intended results.

As with all investments, you may lose money by investing in the Fund.

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BAR CHART AND PERFORMANCE INFORMATION

No performance information is available for the Fund because it has not yet been in operation for a full calendar year.

INVESTMENT ADVISER

AllianceBernstein L.P. is the investment adviser for the Fund.

PORTFOLIO MANAGERS

The following table lists the persons responsible for day-to-day management of the Fund's portfolio:

Employee	Length of Service	Title
Dev Chakrabarti	Since April 2015	Senior Vice President of the Adviser
Mark Phelps	Since April 2015	Senior Vice President of the Adviser

PURCHASE AND SALE OF FUND SHARES

Purchase Minimums

	Initial	Subsequent
Class A/Class C Shares, including traditional IRAs and Roth IRAs	$2,500	$50
Automatic Investment Program	No minimum	$50If initial minimum investment isless than $2,500, then $200monthly until account balance reaches $2,500
Advisor Class Shares (only available to fee-based programs or through other limited or special arrangements approved by the Adviser)	None	None
Class A shares are available at NAV, without an initial sales charge, to 401(k) plans, 457 plans, employer-sponsored 403(b) plans, profit-sharing and money purchase pension plans, defined benefit plans, and non-qualified deferred compensation plans where plan level or omnibus accounts are held on the books of the Fund.	None	None

You may sell (redeem) your shares each day the New York Stock Exchange is open. You may sell your shares through your financial intermediary or by mail (AllianceBernstein Investor Services, Inc., P.O. Box 786003, San Antonio, TX 78278-6003) or telephone (800-221-5672).

TAX INFORMATION

The Fund may pay income dividends or make capital gains distributions, which may be subject to federal income taxes and taxable as ordinary income or capital gains, and may also be subject to state and local taxes.

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 or a group retirement plan), the Fund and its related companies 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 financial intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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