SDSI seeks to provide income and capital appreciation by holding a short-duration portfolio of various fixed income securities of any credit quality. The fund may invest in securities issued or guaranteed by the US Treasury and certain US government agencies, bank loans, collateralized debt obligations including mortgage- or asset-backed securities, preferred stocks, and convertibles. To build the portfolio, the fund manager assesses current and anticipated interest rates and economic conditions. The weighted average duration of the resulting portfolio must be three years or shorter. Portfolio securities may be payable in US or foreign currencies. The fund manager may utilize derivatives, such as currency forwards and swaps, and may use currency exchange contracts for hedging purposes or to enhance returns. The fund may engage in active and frequent trading of portfolio securities.