SUMMARY PROSPECTUS November 1, 2023

AB International Low Volatility Equity Portfolio

(formerly, AB International Strategic Core Portfolio)

Ticker: Class A–ISARX; Class C–ISCRX; Advisor Class–ISRYX; Class Z–ISZRX

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 November 1, 2023, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus. For free paper or electronic copies of the Fund’s Prospectus, reports to shareholders and other information about the Fund, go to www.abfunds.com/go/prospectus, email a request to prorequest@alliancebernstein.com, call (800) 227-4618, or ask any financial advisor, bank, or broker-dealer who offers shares of the Fund. The Fund’s reports to shareholders are also available at www.abfunds.com/go/ILVE.

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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, hold and sell shares of the Fund. You may be required to pay commissions and/or other forms of compensation to a broker for transactions in Advisor Class shares, which are not reflected in the tables or the examples below. 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 Funds—Sales Charge Reduction Programs for Class A Shares on page 74 of the Fund’s Prospectus, in Appendix B—Financial Intermediary Waivers of the Fund’s Prospectus and in Purchase of Shares—Sales Charge Reduction Programs for Class A Shares on page 133 of the Fund’s SAI.

Shareholder Fees (fees paid directly from your investment)

	Class A Shares	Class C Shares	Advisor Class Shares	Class Z Shares
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	4.25%	None	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	None
Exchange Fee	None	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		Class Z
Management Fees		.65%		.65%		.65%		.65%
Distribution and/or Service (12b-1) Fees		.25%		1.00%		None		None
Other Expenses:
Transfer Agent		.02%		.04%		.02%		.02%
Other Expenses(c)		.09%		.09%		.09%		.09%
Total Other Expenses		.11%		.13%		.11%		.11%
Total Annual Fund Operating Expenses		1.01%		1.78%		.76%		.76%
Fee Waiver and/or Expense Reimbursement(d)		(.01)%		(.04)%		(.01)%		(.01)%
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement		1.00%		1.74%		.75%		.75%

(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.

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(b) For Class C shares, the CDSC is 0% after the first year. Class C shares automatically convert to Class A shares after eight years.

(c) “Other Expenses” includes acquired fund fees and expenses totaling less than .01%.

(d) The Adviser has contractually agreed to waive its management fees and/or to bear certain expenses of the Fund until October 31, 2024 to the extent necessary to prevent total Fund operating expenses (excluding acquired fund fees and expenses, interest expense, taxes, extraordinary expenses, and brokerage commissions and other transaction costs), on an annualized basis, from exceeding 1.00%, 1.75%, 0.75% and 0.75% of average daily net assets, respectively, for Class A, Class C, Advisor Class and Class Z shares. In addition, in connection with the Fund’s investments in AB Government Money Market Portfolio (the “Money Market Portfolio”) (except for the investment of any cash collateral from securities lending), the Adviser has contractually agreed to waive its management fee from the Fund and/or reimburse other expenses of the Fund in an amount equal to the Fund’s pro rata share of the Money Market Portfolio’s effective management fee. Each of the agreements will remain in effect until October 31, 2024 and may only be terminated or changed with the consent of the Fund’s Board of Directors. In addition, each of the agreements will be automatically extended for one-year terms unless the Adviser provides notice of termination to the Fund at least 60 days prior to the end of the period.

Examples

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 any fee waiver remains 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		Class Z
After 1 Year	$	523	$	278	*	$	77	$	77
After 3 Years	$	732	$	556		$	242	$	242
After 5 Years	$	958	$	961		$	421	$	421
After 10 Years	$	1,608	$	1,888		$	941	$	941

* 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 year, the Fund’s portfolio turnover rate was 42% of the average value of its portfolio.

PRINCIPAL STRATEGIES

The Adviser seeks to achieve the Fund’s investment objective by investing, under normal circumstances, at least 80% of its net assets, including any borrowings for investment purposes, in equity securities of non-U.S. companies, and in companies in at least three countries other than the United States.

The Fund invests in companies that are determined by the Adviser to offer favorable long-term sustainable profitability, price stability, and attractive valuations. The Adviser employs an integrated approach that combines both fundamental and quantitative research to identify attractive investment opportunities. Factors that the Adviser considers in this regard include: a company’s record and projections of profitability, accuracy and availability of information with respect to the company, success and experience of management, competitive advantage, low stock price volatility, and liquidity of the company’s securities. The Adviser compares these results to the characteristics of the general stock markets to determine the relative attractiveness of each company at a given time. The Adviser weighs economic, political and market factors in making investment decisions. The Adviser seeks to manage the Fund so that it is subject to less share price volatility than many other international mutual funds, although there can be no guarantee that the Adviser will be successful in this regard.

The Fund primarily invests in mid- and large-capitalization companies, which are currently defined for the Fund as companies that have market capitalizations of $1.5 billion or more. The Fund’s holdings of non-U.S. companies will generally include some companies located in emerging markets.

Fluctuations in currency exchange rates can have a dramatic impact on the returns of equity securities. The Adviser may adjust the foreign currency exposure resulting from the Fund’s security positions through the use of currency-related derivatives, primarily in an effort to minimize the currency risk to which the Fund is subject. However, the Adviser is not required to use such derivatives.

PRINCIPAL RISKS

• Market Risk: The value of the Fund’s assets will fluctuate as the market or markets in which the Fund invests fluctuate. The value of the Fund’s investments may decline, sometimes rapidly and unpredictably, simply because of economic changes or other events, including public health crises (including the occurrence of a contagious disease or illness) and regional and global conflicts, that affect large portions of the market. It includes the risk that a particular style of investing may be underperforming the market generally.

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• 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 more difficult to trade 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.

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

• 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.

• Derivatives Risk: Derivatives may be difficult to price or unwind and leveraged so that small changes may produce disproportionate losses for the Fund. A short position in a derivative instrument involves the risk of a theoretically unlimited increase in the value of the underlying asset, reference rate or index, which could cause the Fund to suffer a potentially unlimited loss. Derivatives, especially over-the-counter derivatives, are also subject to counterparty risk, which is the risk that the counterparty (the party on the other side of the transaction) on a derivative transaction will be unable or unwilling to honor its contractual obligations to the Fund.

• 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. Some of these techniques may incorporate, or rely upon, quantitative models, but there is no guarantee that these models will generate accurate forecasts, reduce risk or otherwise perform as expected.

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

BAR CHART AND PERFORMANCE INFORMATION

The bar chart and performance information provide an indication of the historical risk of an investment in the Fund by showing:

• how the Fund’s performance changed from year to year over the life of the Fund; and

• how the Fund’s average annual returns for one year, five years and since inception compare to those of a broad-based securities market index.

You may obtain updated performance information on the Fund’s website at www.abfunds.com (click on “Investments—Mutual Funds”).

The Fund’s past performance before and after taxes, of course, does not necessarily indicate how it will perform in the future.

Bar Chart

The annual returns in the bar chart are for the Fund’s Class A shares and do not reflect sales loads. If sales loads were reflected, returns would be less than those shown. Through September 30, 2023, the year-to-date unannualized return for Class A shares was 3.49%.

During the period shown in the bar chart, the Fund’s:

Best Quarter was up 13.45%, 2nd quarter, 2020; and Worst Quarter was down -19.90%, 1st quarter, 2020.

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Performance Table

Average Annual Total Returns

(For the periods ended December 31, 2022)

		1 Year		5 Years		Since Inception*
Class A**	Return Before Taxes		-18.47%		0.16%		2.81%
	Return After Taxes on Distributions		-18.47%		-0.03%		2.57%
	Return After Taxes on Distributions and Sale of Fund Shares		-10.94%		0.19%		2.21%
Class C	Return Before Taxes		-16.36%		0.27%		2.63%
Advisor Class	Return Before Taxes		-14.65%		1.29%		3.66%
Class Z	Return Before Taxes		-14.65%		1.29%		3.67%
MSCI EAFE Index (reflects no deduction for fees, expenses or taxes)			-14.45%		1.54%		3.24%

* Inception dates: 7/29/15 for Class A, Class C and Advisor Class shares and 11/20/19 for Class Z shares. Performance information for periods prior to the inception of Class Z shares is the performance of the Fund’s Class A shares adjusted to reflect the expenses of the Class Z shares.

** After-tax Returns:

– Are shown for Class A shares only and will vary for the other Classes of shares because these Classes have different expense ratios;

– Are an estimate, which is based on the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes; actual after-tax returns depend on an individual investor’s tax situation and are likely to differ from those shown; and

– Are not relevant to investors who hold Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.

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
Kent W. Hargis	Since 2015	Senior Vice President of the Adviser
Brian Holland	Since January 2023	Senior Vice President of the Adviser
Sammy Suzuki*	Since 2015	Senior Vice President of the Adviser

* Mr. Suzuki is expected to relinquish his role as portfolio manager of the Fund effective December 31, 2023.

PURCHASE AND SALE OF FUND SHARES

Purchase Minimums

The following table describes the initial and subsequent minimum purchase amounts for each class of shares, which are subject to waiver in certain circumstances.

	Initial	Subsequent
Class A/Class C shares, including traditional IRAs and Roth IRAs	$2,500	$50
Automatic Investment Program	None	$50 If initial minimum investment is less than $2,500, then $200 monthly until account balance reaches $2,500
Advisor Class shares (only available to fee-based programs or through other limited arrangements and certain commission-based brokerage arrangements)	None	None
Class A and Class Z shares are available at net asset value, 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 and, for Class Z shares, to persons participating in certain fee-based programs sponsored by a financial intermediary, where in each case plan level or omnibus accounts are held on the books of the Fund.	None	None

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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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