MainStay Large Cap Growth Fund (Prospectus Summary) | MainStay Large Cap Growth Fund

MainStay Large Cap Growth Fund

Investment Objective

The Fund seeks long-term growth of capital.

Fees and Expenses of the Fund

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund.

The Fund is closed to new investors, with certain exceptions. Please see page 59 of the Prospectus for additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Class R6
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lesser of the original offering price or redemption proceeds)	none

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

Annual Fund Operating Expenses		Class R6
Management Fees (as an annual percentage of the Fund's average daily net assets)	[1]	0.61%
Distribution and/or Service (12b-1) Fees		none
Other Expenses		0.02%
Total Annual Fund Operating Expenses		0.63%

Example

The Example is intended to help you compare the cost of investing in the Fund with the cost 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. The Example also assumes 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 your costs would be:

Expense Example (USD $)	Expense Example, With Redemption, 1 Year	Expense Example, With Redemption, 3 Years	Expense Example, With Redemption, 5 Years	Expense Example, With Redemption, 10 Years
Class R6	64	202	351	786

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 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 60% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Fund invests at least 80% of its assets (net assets plus any borrowings for investment purposes) in large capitalization companies, which are companies having a market capitalization in excess of $4 billion at the time of purchase. Typically, Winslow Capital Management, LLC, the Fund's Subadvisor, invests substantially all of the Fund's investable assets in domestic securities. However, the Fund is permitted to invest up to 20% of its net assets in foreign securities, which are generally securities issued by companies organized outside the U.S. and traded primarily in markets outside the U.S.

Investment Process: The Fund invests in those companies that the Subadvisor believes will provide an opportunity for achieving superior portfolio returns (i.e., returns in excess of the returns of the average stock mutual fund) over the long term. The Subadvisor seeks to invest in companies that have the potential for above-average future earnings growth with management focused on shareholder value.

When purchasing stocks for the Fund, the Subadvisor looks for companies typically having some or all of the following attributes: addressing markets with growth opportunities; favorable market share; identifiable and sustainable competitive advantages; a management team that can perpetuate the firm's competitive advantages; and, attractive, and preferably rising, returns on invested capital.

The Subadvisor takes a "bottom-up" investment approach when selecting investments. This means it bases investment decisions on company specific factors, not general economic conditions.

Under normal market conditions, the Subadvisor employs a sell discipline pursuant to which it may sell some or all of its position in a stock when a stock becomes fully valued, the fundamental business prospects are deteriorating, or the position exceeds limits set by the Subadvisor.

Principal Risks

Loss of Money Risk: Before considering an investment in the Fund, you should understand that you could lose money.

Market Changes Risk: The value of the Fund's investments may change because of broad changes in the markets in which the Fund invests, which could cause the Fund to underperform other funds with similar objectives. From time to time, markets may experience periods of acute stress that may result in increased volatility. Such market conditions tend to add significantly to the risk of short-term volatility in the net asset value of the Fund's shares.

Management Risk: The investment strategies, practices and risk analysis used by the Subadvisor may not produce the desired results.

Equity Securities Risk: Investments in common stocks and other equity securities are particularly subject to the risk of changing economic, stock market, industry and company conditions and the risks inherent in the portfolio managers' ability to anticipate such changes that can adversely affect the value of the Fund's holdings. Opportunity for greater gain often comes with greater risk of loss.

Growth Stock Risk: If growth companies do not increase their earnings at a rate expected by investors, the market price of the stock may decline significantly, even if earnings show an absolute increase. Growth company stocks also typically lack the dividend yield that can cushion stock prices in market downturns.

Foreign Securities Risk: Investments in foreign securities may be riskier than investments in U.S. securities. Differences between U.S. and foreign regulatory regimes and securities markets, including less stringent investor protections and disclosure standards of some foreign markets, less liquid trading markets and political and economic developments in foreign countries, may affect the value of the Fund's investments in foreign securities. Foreign securities may also subject the Fund's investments to changes in currency rates. These risks may be greater with respect to securities of companies that conduct their business activities in emerging markets or whose securities are traded principally in emerging markets.

Past Performance

The following bar chart and tables indicate some of the risks of investing in the Fund. The bar chart shows you how the Fund's calendar year performance has varied over the last ten years. The average annual total returns table shows how the Fund's average annual total returns (before and after taxes) for the one-, five- and ten-year periods compare to those of two broad-based securities market indices. The Fund has selected the Russell 1000^® Growth Indexas its primary benchmark. The Russell 1000^® Growth Index measures the performance of the large-cap growth segment of the U.S. equity universe. It includes those Russell 1000^® Index companies with higher price-to-book ratios and higher forecasted growth values. The Fund has selected the Standard & Poor’s 500^® Index (“S&P 500^® Index”) as a secondary benchmark. The S&P 500^® Index is widely regarded as the standard index for measuring large-cap U.S. stock market performance.

Performance data for the classes varies based on differences in their fee and expense structures. Performance figures for Class R6 shares, first offered on June 17, 2013, include the historical performance of Class I shares. Performance for Class I shares, which were first offered on April 1, 2005, include the historical performance of Class A shares through March 31, 2005, adjusted for differences in fees and expenses. Performance figures for Class A shares include the historical performance of the FMI Winslow Growth Fund (a Predecessor to the Fund) through March 31, 2005, adjusted to reflect the current maximum sales charge applicable to the Class A shares. Unadjusted, the performance for Class I shares would likely have been different. Performance for Class R6 shares would also likely have been different because of differences in expenses attributable to each share class. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Please visit mainstayinvestments.com for more recent performance information.

The bar chart shows you how the Fund's calendar year performance has varied over the last ten years.

Annual Returns, Class R6 Shares (by calendar year 2003-2012)

Best Quarter
2Q/03	18.28	%
Worst Quarter
4Q/08	-22.49	%

As of March 31, 2013, the Class R6 shares of the Fund would have had a year-to-date return of 9.40%.

Average Annual Total Returns (for the periods ended December 31, 2012)

Average Annual Total Returns

Average Annual Returns, Label

Average Annual Returns, 1 Year

Average Annual Returns, 5 Years

Average Annual Returns, 10 Years

Class R6

Class R6 Return Before Taxes

13.21%

2.39%

9.41%

Class R6 After Taxes on Distributions

Class R6 Return After Taxes on Distributions

13.16%

2.31%

9.36%

Class R6 After Taxes on Distributions and Sales

Class R6 Return After Taxes on Distributions and Sale of Fund Shares

8.66%

2.04%

8.39%

Russell 1000 Growth Index

Russell 1000® Growth Index (reflects no deductions for fees, expenses, or taxes)

15.26%

3.12%

7.52%

S&P 500 Index

S&P 500® Index (reflects no deductions for fees, expenses, or taxes)

16.00%

1.66%

7.10%

After-tax returns are calculated using the highest individual federal marginal income tax rates in effect at the time of each distribution or capital gain or upon the sale of fund shares, and do not reflect the impact of state and local taxes. In some cases, the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of shares at the end of the measurement period. Actual after-tax returns depend on your tax situation and may differ from those shown. After-tax returns are not relevant if you hold your shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns shown are for Class R6 shares. After-tax returns for the other share classes may vary.

[1] The management fee is as follows: 0.75% on assets up to $500 million; 0.725% on assets from $500 million to $750 million; 0.71% on assets from $750 million to $1 billion; 0.70% on assets from $1 billion to $2 billion; 0.66% on assets from $2 billion to $3 billion; 0.61% on assets from $3 billion to $7 billion; 0.585% on assets from $7 billion to $9 billion; and 0.575% on assets in excess of $9 billion.