This chapter discusses private equity funds. It looks at the typical fund structures, who invests in private equity, and compares and contrasts alternative investment options. A private equity fund is a form of ‘investment club’ in which the principal investors are institutional investors, such as pension funds, investment funds, endowment funds, insurance companies, banks, sovereign wealth funds, family offices/high net worth individuals and funds of funds, as well as the private equity fund managers themselves. Private equity funds have a limited life, meaning that there is a pre-agreed date on which they will stop making new investments and subsequently be wound up. Typically, a fund invests in new projects for six years and is wound up in ten years. There is a standard extension period of two years in most fund agreements, hence they are generally known as ‘ten plus two’ limited life funds. In the past few years, some longer-term funds have started to be raised by some fund managers. These are typically targeting growth capital. The chapter then differentiates limited partners (external investors) from the general partner (the manager). It also studies the economics of private equity, examines the details of a representative Limited Partners Agreement as well as taxation, and describes the secondary fund market.