Strategy. MFS (Massachusetts Financial Services Company, the fund's investment adviser) normally invests at least 80% of the funds net assets in debt instruments of issuers that are tied economically to emerging market countries. Emerging markets are countries determined to have emerging market economies based on factors that demonstrate the country's financial and capital markets are in the development phase, including whether a particular country has a low- to middle-income economy according to the International Bank for Reconstruction and Development (the World Bank), the countrys designation by the International Monetary Fund as an emerging market, or the country's inclusion in an emerging market index. Emerging market countries include countries located in Latin America, Asia, Africa, the Middle East, and developing countries of … Show more… MFS (Massachusetts Financial Services Company, the fund's investment adviser) normally invests at least 80% of the funds net assets in debt instruments of issuers that are tied economically to emerging market countries. Emerging markets are countries determined to have emerging market economies based on factors that demonstrate the country's financial and capital markets are in the development phase, including whether a particular country has a low- to middle-income economy according to the International Bank for Reconstruction and Development (the World Bank), the countrys designation by the International Monetary Fund as an emerging market, or the country's inclusion in an emerging market index. Emerging market countries include countries located in Latin America, Asia, Africa, the Middle East, and developing countries of Europe, primarily Eastern Europe. Debt instruments include corporate debt instruments, foreign government securities, U.S. Government securities, and other obligations to repay money borrowed. MFS may also invest the funds assets in debt instruments of issuers that are not tied economically to emerging market countries. MFS may invest up to 100% of the funds assets in below investment grade quality debt instruments. MFS normally invests the fund's assets across different industries, sectors, countries, and regions, but MFS may invest a significant percentage of the funds assets in issuers in a single industry, sector, country, or region. While MFS may use derivatives for any investment purpose, to the extent MFS uses derivatives, MFS expects to use derivatives primarily to increase or decrease exposure to a particular market, segment of the market, or security, to increase or decrease interest rate or currency exposure, or as alternatives to direct investments. Derivatives include futures, forward contracts, options, and swaps. MFS allocates the fund's assets across countries primarily based on fundamental economic and financial analysis of the creditworthiness of each country and the relative values of countries' external debt, currencies, and local market debt. In selecting investments, MFS may consider economic and financial fundamentals, liquidity, duration, yield curve positioning, relative value, and other factors. Quantitative tools that systematically evaluate these and other factors may also be considered. For purposes of the fund's 80% policy, net assets include the amount of any borrowings for investment purposes. Show less