Alger Mid Cap Growth Fund

Summary Prospectus

March 1, 2019	Class	Ticker Symbols
	A	AMGAX
	B	AMCGX
	C	AMGCX

Optional Internet Availability of Alger Shareholder Reports

Beginning on January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Fund’s shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports from the Fund or from your financial intermediary. Instead, the reports will be made available on a website, and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Fund electronically by signing up for paperless delivery at www.icsdelivery.com/alger. If you own these shares through a financial intermediary, contact your financial intermediary.

You may elect to receive all future reports in paper free of charge. You can inform the Fund that you wish to continue receiving paper copies of your shareholder reports by contacting us at 1-866-345-5954 or fundreports.com. If you own these shares through a financial intermediary, contact your financial intermediary to elect to continue to receive paper copies of your shareholder reports. Your election to receive reports in paper will apply to all funds held with the Alger Fund Complex or your financial intermediary.

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, reports to shareholders, and other information about the Fund online at www.alger.com. You can also get this information at no cost by calling (800) 992-3863 or by sending an e-mail request to summaryprospectus@alger.com. The Fund’s Prospectus and Statement of Additional Information, both dated March 1, 2019, are incorporated by reference to this Summary Prospectus, and may be obtained at no cost in the same manner as described above.

Investment Objective

Alger Mid Cap Growth Fund seeks long-term capital appreciation.

Fund Fees and Expenses

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 discounts if you and your family invest, or agree to invest in the future, at least $25,000 in Class A Shares of the Alger Family of Funds, including the Fund. More information about these and other discounts is available from your financial professional and in “Purchasing and Redeeming Fund Shares” on page 67 and in Appendix A – Waivers and Discounts Available from Intermediaries on page A-1 in the Fund’s Prospectus, and in the sections “Right of Accumulation (Class A Shares)” and “Letter of Intent (Class A Shares)” on page 25 of the Fund’s Statement of Additional Information.

	Alger Mid Cap Growth Fund
Class	A	B	C
Shareholder Fees (fees paid directly from your investment)
Maximum sales charge (load) imposed on purchases as a % of offering price	5.25%	None	None
Maximum deferred sales charge (load) as a % of purchase price or redemption proceeds, whichever is lower	None*	5.00%	1.00%
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Advisory Fees	.76%	.76%	.76%
Distribution and/or Service (12b-1) Fees	.25%	1.00%	1.00%
Other Expenses	.29%	.29%	.35%
Total Annual Fund Operating Expenses	1.30%	2.05%	2.11%

* Purchases of $1 million or more of Class A Shares at net asset value may be subject to a contingent deferred sales charge of 1.00% on redemptions made within 12 months of purchase.

Inspired by Change, Driven by Growth.

Alger Mid Cap Growth Fund 2/5

Summary Prospectus

March 1, 2019

Example

The following 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, that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions you would pay the following expenses if you redeemed your shares at the end of each period:

	1 Year	3 Years	5 Years	10 Years
Class A	$650	$915	$1,200	$2,010
Class B	$708	$943	$1,303	$2,187
Class C	$314	$661	$1,134	$2,441
You would pay the following expenses if you did not redeem your shares:
Class B	$208	$643	$1,103	$2,187
Class C	$214	$661	$1,134	$2,441

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 examples, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 125.34% of the average value of its portfolio.

Principal Investment Strategy

Fred Alger Management, Inc. believes companies undergoing Positive Dynamic Change offer the best investment opportunities. Positive Dynamic Change refers to companies realizing High Unit Volume Growth or companies undergoing Positive Lifecycle Change. High Unit Volume Growth companies are traditional growth companies experiencing, for example, rapidly growing demand or market dominance. Positive Lifecycle Change companies are, for example, companies benefitting from new regulations, a new product innovation or new management.

The Fund focuses on mid-sized companies that Fred Alger Management, Inc. believes demonstrate promising growth potential. Under normal circumstances, the Fund invests at least 80% of its net assets in equity securities of companies that, at the time of purchase of the securities, have total market capitalization within the range of companies included in the Russell Midcap Growth Index or the S&P MidCap 400 Index, as reported by the indexes as of the most recent quarter-end. Both indexes are designed to track the performance of medium-capitalization stocks. At December 31, 2018, the market capitalization of the companies in these indexes ranged from $364.58 million to $35.61 billion. Equity securities include common or preferred stocks that are listed on U.S. or foreign exchanges.

The Fund may invest a significant portion of its assets in securities of companies conducting business within a single sector, including the information technology, healthcare, consumer discretionary, and industrials sectors.

The Fund’s portfolio manager(s) may sell a stock when it reaches a target price, it fails to perform as expected, or other opportunities appear more attractive. As a result, the Fund may engage in active trading of portfolio securities.

The Fund can invest in foreign securities.

Principal Risks

An investment in the Fund involves risks. The Fund’s share price may go down, which means you could lose money. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Investment Risk – An investment in the Fund is subject to investment risk, including the possible loss of the entire principal amount that you invest.

Market Risk – Your investment in Fund shares represents an indirect investment in the securities owned by the Fund. The value of these securities, like other investments, may move up or down, sometimes rapidly and unpredictably. Your Fund shares at any point in time may be worth less than what you invested, even after taking into account the reinvestment of Fund dividends and distributions.

Alger Mid Cap Growth Fund 3/5

Summary Prospectus

March 1, 2019

Equity Securities Risk – As with any fund that invests in stocks, your investment will fluctuate in value, and the loss of your investment is a risk of investing. The Fund’s price per share will fluctuate due to changes in the market prices of its investments. Also, the Fund’s investments may not grow as fast as the rate of inflation and stocks tend to be more volatile than some other investments you could make, such as bonds.

Growth Stocks Risk – Prices of growth stocks tend to be higher in relation to their companies’ earnings and may be more sensitive to market, political and economic developments than other stocks, making their prices more volatile. An investment in the Fund may be better suited to investors who seek long-term capital growth and can tolerate fluctuations in their investment’s value.

Mid Cap Securities Risk – There may be greater risk in investing in medium-capitalization companies rather than larger, more established companies due to such factors as inexperienced management and limited product lines or financial resources. It may also be difficult or impossible to liquidate a security position at a time and price acceptable to the Fund because of the potentially less frequent trading of stocks of smaller market capitalization.

Sector Risk – The Fund may have a significant portion of its assets invested in securities of companies conducting business within a single sector. Companies in the same sector may be similarly affected by economic, regulatory, political or market events or conditions, which may make the Fund more vulnerable to unfavorable developments in that sector than a fund that has a more diversified portfolio. Generally, the more broadly the Fund invests, the more it spreads risk and potentially reduces the risks of loss and volatility.

Technology Companies Risk – The Fund may have a significant portion of its assets invested in securities of technology companies. Many technology companies have limited operating histories and prices of these companies’ securities have historically been more volatile than other securities, especially over the short term. Technology companies may also face increased competition, government regulation, and risk of obsolescence due to progress in technological developments.

Healthcare Companies Risk – The Fund may have a significant portion of its assets invested in securities of healthcare companies. At times, the performance of healthcare companies will lag the performance of other industries or the broader market as a whole, and the performance of such companies may be more volatile. Healthcare companies may also be significantly affected by intense competition, aggressive pricing, government regulation, technological innovations, product obsolescence, patent considerations, product compatibility and consumer preferences.

Portfolio Turnover (Active Trading) Risk – Because the Fund may engage in active trading of portfolio securities, it may incur increased transaction costs and brokerage commissions, both of which can lower the actual return on an investment. Active trading may also increase short-term gains and losses, which may affect the taxes a shareholder has to pay.

Foreign Securities Risk – The Fund’s performance will be influenced by political, social and economic factors affecting investments in foreign companies. Special risks associated with investments in companies include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political instability and differing audit and legal standards.

Performance

The following bar chart and the table beneath it provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s average annual returns for the indicated periods compare with those of an appropriate benchmark of market performance. Performance in the bar chart does not reflect the effect of the sales charge imposed on purchases of Class A Shares of the Fund. If the bar chart reflected the applicable sales charges, returns would be less than those shown. The Fund’s past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. Updated performance information is available on the Fund’s website www.alger.com.

Alger Mid Cap Growth Fund 4/5

Summary Prospectus

March 1, 2019

Annual Total Return for Class A Sharesas of December 31 (%)

Best Quarter: Q2 2009 19.64% Worst Quarter: Q3 2011 -23.83%

Average Annual Total Return as of December 31, 2018

	1 Year	5 Years	10 Years	Since 12/31/96*
Class A (Inception 12/31/96)
Return Before Taxes	-12.25%	3.94%	12.12%	7.70%
Return After Taxes on Distributions	-13.53%	3.60%	11.93%	6.20%
Return After Taxes on Distributions and Sale of Shares	-6.09%	3.03%	10.14%	5.76%
Class B (Inception 5/24/93)
Return Before Taxes	-12.32%	3.98%	12.03%	7.66%
Class C (Inception 7/31/97)
Return Before Taxes	-9.00%	4.20%	11.75%	7.09%
Russell Midcap Growth Index (reflects no deductions for fees, expenses or taxes)	-4.75%	7.42%	15.12%	8.31%

* Performance of the Fund’s Class C Shares prior to July 31, 1997 reflects the performance of the Fund’s Class A Shares, as adjusted with currently applicable sales charges and operating expenses, which differ from historical charges and expenses. Since-inception performance of the Fund’s Class B Shares is available upon request.

In the foregoing table, 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. The after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns for Class B and C Shares, which are not shown, will vary from those shown for Class A Shares. A “Return After Taxes on Distributions and Sale of Fund Shares” may sometimes be higher than the other two return figures; this happens when there is a capital loss on redemptions, giving rise to a tax benefit to the shareholder.

Alger Mid Cap Growth Fund 5/5

Summary Prospectus

March 1, 2019

Management

Investment Manager	Portfolio Managers Jointly and Primarily Responsible for Day-to-Day Management of the Fund’s Portfolio
Fred Alger Management, Inc.	Dan C. Chung, CFA Chief Executive Officer, Chief Investment Officer and Portfolio Manager Since January 2018
	Teresa McRoberts Senior Vice President, Since February 2013 Senior Analyst and Portfolio Manager Since February 2015

Shareholder Information

Purchasing and Redeeming Fund Shares

Class B Shares of the Fund are closed to new accounts.

Minimum Investments: the following minimums apply to an account in the Fund, whether invested in Class A, Class B or Class C Shares.

Type of Account	Initial Investment	Subsequent Investment
Regular account	$1,000	$50
Retirement Accounts (including IRAs)	500	50
Automatic Investment	500	50
Asset-based Fee Program Accounts	250	50

Minimums may be waived in certain circumstances. See “Additional Information about Minimum Initial Investments” in the Prospectus.

In general, investors may purchase or redeem Fund shares on any business day by mail (DST Asset Manager Solutions, Inc., Attn: The Alger Funds, PO Box 219432 Kansas City, MO 64121-9432), online at www.alger.com, by telephone 1(800) 992-3863, or through a financial intermediary.

Investors who wish to purchase, exchange or redeem Fund shares through a financial intermediary should contact their financial intermediary directly.

Tax Information

The Fund’s distributions may be taxable as ordinary income or capital gains.

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), the Fund and/or its Manager or Distributor 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 financial advisor to recommend the Fund over another investment. Ask your financial advisor or visit your financial intermediary’s website for more information.

Fred Alger & Company, Incorporated 360 Park Avenue South, New York, NY 10010 / 800.992.3863 / www.alger.com

Mid CapABC 3119

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