MFSB seeks total return through an actively managed, broad portfolio of debt securities. The fund invests in US and foreign government securities, municipal instruments, mortgage- and asset-backed securities, and corporate bonds. The portfolio includes debt instruments of any geographic location, maturity, and credit quality, focusing on investment grade debts. To construct the portfolio, the fund employs an active bottom-up approach, selecting investments based on fundamental analysis of individual instruments and issuers. The adviser also considers top-down factors in structuring the fund. The funds assets are diversified across industries and sectors, but may be concentrated in a single sector or a few issuers. Derivatives such as futures, forward contracts, options, and swaps may be used to adjust market and interest rate exposure or as alternatives to direct investments.