A Fund of Funds (FOF) is a type of investment structure that collects money from investors and then uses that money to buy other types of investments. Instead of investing directly in stocks, bonds, commodities, ETFs and other investments, investors in a FOF buy into the FOF itself which then invests in a variety of other funds. That way, a FOF acts like a one-stop shop for investing, letting you invest in a diverse range of investments through a single fund.