Eaton Vance Tax-Managed Buy-Write Income Fund is a United States-based diversified closed-controlled investment company. The fund's investment objective is to provide current income and gains, with a secondary objective of capital appreciation. It invests in a diversified portfolio of common stocks and writes call options on one or more U.S. indices on a substantial portion of the value of its common stock portfolio to generate current earnings from the option premium. Its portfolio of investments consists of aerospace and defense, banks, biotechnology, chemicals, consumer finance, industrial conglomerates, food, and staples retailing.