MainStay Global High Income Fund (Prospectus Summary) | MainStay Global High Income Fund

MainStay Global High Income Fund

Investment Objective

The Fund seeks maximum current income by investing in high-yield debt securities
of non-U.S. issuers.

Capital appreciation is a secondary objective.

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. You may qualify for sales charge discounts if you and
your family invest, or agree to invest in the future, at least $50,000 in the
MainStay Funds. This amount may vary depending on the MainStay Fund in which you
invest. More information about these and other discounts is available from your
financial professional and in the "Information on Sales Charges" section
starting on page 94 of the Prospectus and in the "Alternative Sales
Arrangements" section on page 104 of the Statement of Additional Information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees MainStay Global High Income Fund	Investor Class		Class A		Class B	Class C	Class I
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	4.50%		4.50%		none	none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lesser of the original offering price or redemption proceeds)	none	[1]	none	[1]	5.00%	1.00%	none

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

Annual Fund Operating Expenses MainStay Global High Income Fund		Investor Class	Class A	Class B	Class C	Class I
Management Fees (as an annual percentage of the Fund's average daily net assets)	[1]	0.72%	0.72%	0.72%	0.72%	0.72%
Distribution and/or Service (12b-1) Fees		0.25%	0.25%	1.00%	1.00%	none
Other Expenses		0.35%	0.25%	0.35%	0.35%	0.25%
Total Annual Fund Operating Expenses		1.32%	1.22%	2.07%	2.07%	0.97%

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 (except as indicated with respect to
Class B and Class C shares). The Example reflects Class B shares converting into
Investor Class shares in years 9-10; fees could be lower if you are eligible to
convert to Class A shares instead. 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 MainStay Global High Income Fund (USD $)	Investor Class	Class A	Class B	Class C	Class I
Expense Example, With Redemption, 1 Year	578	569	710	310	99
Expense Example, With Redemption, 3 Years	849	820	949	649	309
Expense Example, With Redemption, 5 Years	1,141	1,090	1,314	1,114	536
Expense Example, With Redemption, 10 Years	1,969	1,861	2,208	2,400	1,190

Expense Example, No Redemption MainStay Global High Income Fund (USD $)	Class B	Class C
Expense Example, No Redemption, 1 Year	210	210
Expense Example, No Redemption, 3 Years	649	649
Expense Example, No Redemption, 5 Years	1,114	1,114
Expense Example, No Redemption, 10 Years	2,208	2,400

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 65%
of the average value of its portfolio.

Principal Investment Strategies

The Fund, under normal circumstances, invests in securities rated below
investment grade at levels at least equal to the percentage of below investment
grade debt found in the Fund's primary benchmark. Below investment grade
securities are generally securities that receive low ratings from independent
rating agencies, such as rated lower than BBB by Standard & Poor's and Baa3 by
Moody's Investor Service, Inc., or if unrated, are deemed to be of comparable
quality by the Fund's Subadvisor, MacKay Shields LLC. Some securities rated below
investment grade by independent rating agencies are commonly referred to as "junk
bonds." If independent rating agencies assign different ratings to the same security,
the Fund will use the lower rating for purposes of determining the security's credit
quality.

Normally, the Fund will invest a significant amount of its assets (at least 40%,
unless the Subadvisor deems market conditions to be unfavorable, in which case
the Fund will invest at least 30%) in securities issued by governments, their
agencies and authorities, and corporations that are located in at least three
different foreign countries. The Fund principally invests in countries that are
considered emerging markets, but may invest in countries with established
economies that the Subadvisor believes present favorable conditions. Some of the
foreign securities in which the Fund invests may be denominated in foreign
currency.

The Fund's principal investments include Yankee (dollar-denominated) debt
securities, Brady Bonds, variable rate notes, mortgage-related and asset-backed
securities and mortgage dollar rolls. The Fund may also invest in derivative
instruments, such as floaters, including inverse floaters, forward commitments,
futures, options and swaps agreements to try to enhance returns or reduce the
risk of loss of (hedge) certain of its holdings. The Fund may invest up to 15%
of its total assets in swaps, including credit default swaps. The Fund is
"non-diversified" which means that it may invest a greater percentage of its
assets than other funds in a particular issuer.

The Fund may buy and sell currency on a spot basis, buy foreign currency
options, and enter into foreign currency forward contracts. These techniques may
be used for any legally permissible purpose, including to increase the Fund's
return.

Investment Process: The Subadvisor identifies investment opportunities by
beginning with country selection, then assessing local currencies for upside
potential and downside risk and finally, evaluating specific securities based on
the financial condition and competitiveness of the issuer. The Subadvisor
considers factors such as prospects for a country's political stability,
currency exchange rates, interest rates, inflation, relative economic growth and
governmental policies.

The Subadvisor may sell a security if it no longer believes the security will
contribute to meeting the investment objective of the Fund. In considering
whether to sell a security, the Subadvisor may evaluate, among other things, the
condition of foreign economies and meaningful changes in the issuer's financial
condition and competitiveness.

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 Fund's Subadvisor may not produce the desired results.

Debt Securities Risk: The risks of investing in debt securities include (without
limitation): (i) credit risk, i.e., the issuer may not repay the loan created by
the issuance of that debt security; (ii) maturity risk, i.e., a debt security
with a longer maturity may fluctuate in value more than one with a shorter
maturity; (iii) market risk, i.e., low demand for debt securities may negatively
impact their price; (iv) interest rate risk, i.e., when interest rates go up,
the value of a debt security goes down, and when interest rates go down, the
value of a debt security goes up; (v) selection risk, i.e., the securities
selected by the Subadvisor may underperform the market or other securities
selected by other funds; and (vi) call risk, i.e., during a period of falling
interest rates, the issuer may redeem a security by repaying it early, which may
reduce the Fund's income, if the proceeds are reinvested at lower interest
rates.

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,
as well as 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.

Emerging Markets Risk: The risks related to investing in foreign securities are
generally greater with respect to securities of companies that conduct their
business activities in emerging markets or whose securities are traded
principally in emerging markets. The risks of investing in emerging markets
include the risks of illiquidity, increased price volatility, smaller market
capitalizations, less government regulation, less extensive and less frequent
accounting, financial and other reporting requirements, risk of loss resulting
from problems in share registration and custody, substantial economic and
political disruptions and the nationalization of foreign deposits or assets.

High-Yield Securities Risk: Investments in high-yield securities (commonly
referred to as "junk bonds") are sometimes considered speculative because they
present a greater risk of loss than higher quality securities. Such securities
may, under certain circumstances, be less liquid than higher rated securities.
These securities pay investors a premium (a high interest rate or yield) because
of the increased risk of loss. These securities can also be subject to greater
price volatility. In times of unusual or adverse market, economic or political
conditions, these securities may experience higher than normal default rates.
  
Mortgage-Backed/Asset-Backed Securities Risk: Prepayment risk is associated with
mortgage-backed and asset-backed securities. If interest rates fall, the
underlying debt may be repaid ahead of schedule, reducing the value of the
Fund's investments. If interest rates rise, there may be fewer prepayments,
which would cause the average bond maturity to rise, increasing the potential
for the Fund to lose money. The value of these securities may be significantly
affected by changes in interest rates, the market's perception of issuers, and
the creditworthiness of the parties involved. The ability of the Fund to
successfully utilize these instruments may depend on the ability of the
Subadvisor to forecast interest rates and other economic factors correctly.
These securities may have a structure that makes their reaction to interest rate
changes and other factors difficult to predict, making their value highly
volatile.

Mortgage Dollar Roll Transaction Risk: Mortgage dollar roll transactions are
subject to certain risks, including the risk that securities returned to the
Fund at the end of the roll, while substantially similar, may be inferior to
what was initially sold to the counterparty.

Floaters and Variable Rate Notes Risk: Floaters and variable rate notes provide
for a periodic adjustment in the interest rate paid on the securities. The rate
adjustment intervals may be regular and range from daily up to annually, or may
be based on an event, such as a change in the prime rate. Floating and variable
rate notes may be subject to greater liquidity risk than other debt securities,
meaning that there may be limitations on the Fund's ability to sell the
securities at any given time. Securities with floating interest rates generally
are less sensitive to interest rate changes, but may decline in value if their
interest rates do not rise as much or as fast as interest rates in general. Such
securities also may lose value.

Derivatives Risk: Derivatives are investments whose value depends on (or is
derived from) the value of an underlying instrument, such as a security, asset,
reference rate or index. Derivative strategies often involve leverage, which may
exaggerate a loss, potentially causing the Fund to lose more money than it would
have lost had it invested in the underlying instrument. Derivatives may be
difficult to sell, unwind or value. Derivatives may also be 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 to
honor its contractual obligations to the Fund. Swap transactions tend to shift
the Fund's investment exposure from one type of investment to another, and
therefore entail the risk that a party will default on its payment obligations
to the Fund. Futures may be more volatile than direct investments in the
instrument underlying the futures, and may not correlate perfectly to the
underlying instrument. Futures also may involve a small initial investment
relative to the risk assumed, which could result in losses greater than if they
had not been used. Due to fluctuations in the price of the underlying security,
the Fund may not be able to profitably exercise an option and may lose its
entire investment in an option. Forward commitments entail the risk that the
instrument may be worth less when it is issued or received than the price the
Fund agreed to pay when it made the commitment. The use of foreign currency
forwards may result in currency exchange losses due to fluctuations in currency
exchange rates or an imperfect correlation between portfolio holdings
denominated in a particular currency and the forward contracts entered into by
the Fund.

Non-Diversification Risk: Because the Fund is "non-diversified," it may be more
susceptible than diversified funds to risks associated with an individual
issuer, and to single economic, political or regulatory occurrences.

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. Sales loads are not reflected in the bar chart.
If they were, returns would be less than those shown. 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 a
broad-based securities market index. The Fund has selected the JPMorgan EMBI
Global Diversified Index as its primary benchmark. The JPMorgan EMBI Global
Diversified Index is a market capitalization weighted, total return index
tracking the traded market for U.S. dollar-denominated Brady Bonds, Eurobonds,
traded loans and local market debt instruments issued by sovereign and
quasi-sovereign entities.

Performance data for the classes varies based on differences in their fee and
expense structures. Class I shares were first offered to the public on August
31, 2007. Performance figures for Class I shares include the historical
performance of Class A shares through August 30, 2007. Performance figures for
Investor Class shares, which were first offered on February 28, 2008, include
the historical performance of Class A shares through February 27, 2008.
Performance for newer share classes is adjusted for differences in fees and
expenses. Unadjusted, the performance shown for the newer classes might have
been lower. 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. Sales loads are not reflected in the bar chart. If they were, returns would be
less than those shown.

Annual Returns, Class B Shares (by calendar year 2002-2011)

Best Quarter    
3Q/09    13.07 %
Worst Quarter   
4Q/08    -8.94 %

Average Annual Total Returns (for the periods ended December 31, 2011)

Average Annual Total Returns MainStay Global High Income Fund	Average Annual Returns, Label	Average Annual Returns, 1 Year	Average Annual Returns, 5 Years	Average Annual Returns, 10 Years
Investor Class	Investor Class Return Before Taxes	(0.69%)	5.86%	10.44%
Class A	Class A Return Before Taxes	(0.57%)	5.96%	10.49%
Class B	Class B Return Before Taxes	(1.54%)	5.73%	10.13%
Class C	Class C Return Before Taxes	2.32%	6.05%	10.13%
Class I	Class I Return Before Taxes	4.37%	7.22%	11.28%
After Taxes on Distributions Class B	Class B Return After Taxes on Distributions	(3.52%)	3.49%	7.61%
After Taxes on Distributions and Sales Class B	Class B Return After Taxes on Distributions and Sale of Fund Shares	(0.57%)	3.63%	7.35%
JPMorgan EMBI Global Diversified Index	JPMorgan EMBI Global Diversified Index (reflects no deductions for fees, expenses, or taxes)	7.35%	7.87%	10.62%

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. 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 B shares.
After-tax returns for the other share classes may vary.

[1] A contingent deferred sales charge of 1.00% may be imposed on certain redemptions made within one year of the date of purchase on shares that were purchased without an initial sales charge.

[1] The management fee is as follows: 0.70% on assets up to $500 million and 0.65% on assets in excess of $500 million, plus a fee for fund accounting services previously provided by New York Life Investment Management LLC ("New York Life Investments") under a separate fund accounting agreement. This addition to the management fee amounted to 0.02% of the Fund's average daily net assets, but did not result in a net increase in Total Annual Fund Operating Expenses.