cmsprospectus.htm

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 and other information about the fund, including the fund’s statement of additional information, online at funds.mfs.com. You can also get this information at no cost by calling 1-800-225-2606 or by sending an e-mail request to orderliterature@mfs.com. The fund’s prospectus and statement of additional information, both dated May 31, 2010, as may be supplemented from time to time, are incorporated by reference into this Summary Prospectus.

CLASS	TICKER SYMBOL
Class A (Currently Not Offered)	MCSAX
Class B (Currently Not Offered)	N/A
Class C (Currently Not Offered)	N/A
Class I	MCSIX
Class R1 (Currently Not Offered)	N/A
Class R2 (Currently Not Offered)	N/A
Class R3 (Currently Not Offered)	N/A
Class R4 (Currently Not Offered)	N/A

You may qualify for sales charge reductions if you and certain members of your family invest, or agree to invest in the future, at least $50,000 in MFS Funds. More information about these and other waivers and reductions is available from your financial intermediary and in “Sales Charges and Waivers or Reductions” on page 9 of the fund’s prospectus and “Waivers of Sales Charges” on page 23 of the fund’s statement of additional information Part I.

Share Class	A	B	C	I	ALL R
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	5.75%	N/A	N/A	N/A	N/A
Maximum Deferred Sales Charge (Load) (as a percentage of original purchase price or redemption proceeds, whichever is less)	1.00% #	4.00%	1.00%	N/A	N/A

Share Class	A	B	C	I	R1	R2	R3	R4
Management Fee	0.75%	0.75%	0.75%	0.75%	0.75%	0.75%	0.75%	0.75%
Distribution and/or Service (12b-1) Fees	0.25%	1.00%	1.00%	N/A%	1.00%	0.50%	0.25%	N/A
Other Expenses	0.09%	0.09%	0.09%	0.09%	0.09%	0.09%	0.09%	0.09%
Total Annual Fund Operating Expenses	1.09%	1.84%	1.84%	0.84%	1.84%	1.34%	1.09%	0.84%

#	On shares purchased on or after September 1, 2008, without an initial sales charge and redeemed within 24 months of purchase.

This 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 you redeem your shares at the end of the time periods (unless otherwise indicated); your investment has a 5% return each year; and the fund’s operating expenses remain the same.

	1 YEAR		3 YEARS
Class A Shares	$	680	$	902
Class B Shares assuming
redemption at end of period	$	587	$	879
no redemption	$	187	$	579
Class C Shares assuming
redemption at end of period	$	287	$	579
no redemption	$	187	$	579
Class I Shares	$	86	$	268
Class R1 Shares	$	187	$	579
Class R2 Shares	$	136	$	425
Class R3 Shares	$	111	$	347
Class R4 Shares	$	86	$	268

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 shares are held in a taxable account. These transaction costs, which are not reflected in “Annual Fund Operating Expenses” or in the “Example,” affect the fund’s performance.

MFS (Massachusetts Financial Services Company, the fund's investment adviser) attempts to achieve the fund’s objective by providing exposure to the commodities markets. The fund normally invests significantly in commodity-linked derivatives and debt instruments. Commodities are assets with tangible properties, including oil, natural gas, agricultural products, and industrial and other precious metals. The fund’s investments in commodity-linked derivatives provide exposure to the investment returns of the commodities markets without investing directly in commodities.

MFS primarily invests the fund’s investments in commodity-linked derivatives in commodity-linked notes, but may also invest in other commodity-linked derivatives, such as commodity-linked futures, options, and swaps. In addition to direct investments in commodity-linked derivatives, MFS may also invest up to 25% of the fund’s assets in a wholly-owned and controlled subsidiary (“Subsidiary”) that will invest primarily in commodity-linked derivatives (such as commodity-linked futures, options, and swaps) and debt instruments.

Of the fund’s investments in debt instruments, MFS generally invests substantially all of these investments in investment grade debt instruments.

The fund is a non-diversified fund. This means that MFS may invest a relatively large percentage of the fund’s assets in a single issuer or a small number of issuers.

MFS may use derivatives for any investment purpose. Derivatives include futures, forward contracts, options, structured securities, inverse floating rate instruments, swaps, caps, floors, and collars.

MFS allocates the fund’s investments in commodity-linked derivatives among a variety of different commodity sectors based on quantitative analysis.

MFS uses a bottom-up investment approach to buying and selling debt investments for the fund. Investments are selected primarily based on fundamental analysis of individual instruments and their issuers. Factors considered may include the instrument’s credit quality, collateral characteristics, and indenture provisions, and the issuer’s management ability, capital structure, leverage, and ability to meet its current obligations. Quantitative models that systematically evaluate the structure of the instrument and its features may also be considered.

As with any mutual fund, the fund may not achieve its objective and/or you could lose money on your investment in the fund. An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

Commodity Risk: The value of commodities may be more volatile than the value of equity securities or debt instruments and their value may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity. The price of a commodity may be affected by demand/supply imbalances in the market for the commodity. To the extent the fund focuses its investments in a particular asset of the commodities market, the fund will be more susceptible to risks associated with that particular asset.

Commodity-Linked Note Risk: Commodity-linked notes have characteristics of debt instruments and derivatives and are subject to the risks associated with investing in those types of investments. Commodity-linked notes can be highly volatile and less liquid than other types of investments.

Derivatives Risk: Derivatives can be used to take both long and short positions (i.e., the value of a derivative can be positively or negatively related to the value of the underlying indicator(s) on which the derivative is based). Derivatives can be highly volatile and involve risks in addition to the risks of the underlying indicator(s). Gains or losses from derivatives can be substantially greater than the derivatives’ original cost and can involve leverage.

MFS Commodity Strategy Fund

Tax Risk: In order to qualify as a regulated investment company (RIC) under the Internal Revenue Code (Code), the fund must meet certain requirements regarding the source of its income, the diversification of its assets, and the distribution of its income. If the fund fails to qualify as a RIC and become subject to federal income tax, shareholders of the fund would be subject to the risk of diminished returns.

Interest Rate Risk: The price of a debt instrument falls when interest rates rise and rises when interest rates fall. Instruments with longer maturities, or that do not pay current interest, are more sensitive to interest rate changes.

Credit Risk: The price of a debt instrument depends, in part, on the credit quality of the issuer, borrower, counterparty, or underlying collateral and can decline in response to changes in the financial condition of the issuer, borrower, counterparty, or underlying collateral, or changes in specific or general market, economic, industry, political, regulatory, geopolitical, or other conditions.

Subsidiary Risk: The Subsidiary will not be registered as an investment company under the Investment Company Act of 1940 (the “Act”) and will not be subject to all of the investor protections of the Act. Changes in the laws impacting the fund or the Subsidiary could negatively affect the fund and its shareholders. By investing in the Subsidiary, the fund is exposed to all the risks associated with the Subsidiary’s investments.

Foreign Risk: Exposure to foreign markets through issuers or currencies can involve additional risks relating to market, economic, political, regulatory, geopolitical, or other conditions. These factors can make foreign investments, especially those in emerging markets, more volatile and less liquid than U.S. investments. In addition, foreign markets can react differently to these conditions than the U.S. market.

Prepayment/Extension Risk: Instruments subject to prepayment and/or extension can reduce the potential for gain for the instrument’s holders if the instrument is prepaid and increase the potential for loss if the maturity of the instrument is extended.

Inflation-Adjusting Risk: Interest payments on inflation-adjusted debt instruments can be unpredictable and vary based on the level of inflation. If inflation is negative, principal and income can both decline.

Municipal Risk: The price of a municipal instrument can be volatile and significantly affected by adverse tax or court rulings, legislative or political changes, changes in specific or general market and economic conditions, and the financial condition of municipal issuers and insurers. Because many municipal instruments are issued to finance similar projects, conditions in these industries can significantly affect the fund and the overall municipal market.

Leveraging Risk: Leverage involves investment exposure in an amount exceeding the initial investment. Leverage can cause increased volatility by magnifying gains or losses.

Investment Selection Risk: The MFS analysis of an investment can be incorrect and can lead to an investment focus that results in the fund underperforming other funds with similar investment strategies and/or underperforming the markets in which the fund invests.

Counterparty and Third Party Risk: Transactions involving a counterparty or third party other than the issuer of the instrument are subject to the credit risk of the counterparty or third party, and to the counterparty’s or third party’s ability to perform in accordance with the terms of the transaction.

Financial Services Exposure Risk: Events that affect the financial services sector may have a significant adverse effect on the fund.

Liquidity Risk: It may not be possible to sell certain investments, types of investments, and/or segments of the market at any particular time or at an acceptable price.

The bar chart and performance table are not included because the fund has not had a full calendar year of investment operations.

Portfolio Manager	Since	Title
James J. Calmas	2010	Investment Officer of MFS
Benjamin Nastou	2010	Investment Officer of MFS
Natalie I. Shapiro	2010	Investment Officer of MFS
Linda Zhang	2010	Investment Officer of MFS

You may purchase and redeem shares of the fund each day the New York Stock Exchange is open for trading. You may purchase or redeem shares either by having your financial intermediary process your purchase or redemption, or by overnight mail (MFS Service Center, Inc. (MFSC), c/o Boston Financial Data Services, 30 Dan Road, Canton, MA 02021-2809), by mail ([Fund Name], P.O. Box 55824, Boston, MA 02205-5824), by telephone (1-800-225-2606), or via the Internet at mfs.com (MFS Access).

Class	Initial Minimum	Subsequent Minimum
Class A, Class B, Class C	None – automatic investment plans and certain asset-based fee programs $25 – employer-sponsored retirement plans $250 – Traditional and Roth IRAs $1,000 – other accounts	$50 – by check and non-systematic written exchange request, and via MFSC telephone representatives None – other purchases
Class I, Class R1, Class R2, Class R3, Class R4	None	None

If your shares are held in a taxable account, the fund’s distributions are taxable to you, and will be taxed as ordinary income and/or capital gains.

If you purchase shares of the fund through a financial intermediary, the fund, MFS, and MFS’ affiliates may pay the financial intermediary for the sale of shares of a fund and/or the servicing of shareholder accounts. These payments may create a conflict of interest by influencing your financial intermediary to recommend the fund over another investment. Ask your financial intermediary or visit your financial intermediary’s Web site for more information.