Private equity firms

According to an updated 2008 ranking created by industry magazine Private Equity International(published by PEI Media called the PEI 50), the largest private equity firm in the world today is The Carlyle Group, based on the amount of private equity direct-investment capital raised over a five-year window. As ranked in this article, the 10 largest private equity firms in the world are:
The Carlyle Group
Goldman Sachs Principal Investment Area
TPG
Kohlberg Kravis Roberts
CVC Capital Partners
Apollo Management
Bain Capital
Permira
Apax Partners
The Blackstone Group
Because private equity firms are continuously in the process of raising, investing and distributing their private equity funds, capital raised can often be the easiest to measure. Other metrics can include the total value of companies purchased by a firm or an estimate of the size of a firm's active portfolio plus capital available for new investments. As with any list that focuses on size, the list does not provide any indication as to relative investment performance of these funds or managers.
Additionally, Private Equity Intelligence, an independent data provider, ranks the 25 largest private equity investment managers. Among the larger firms in that ranking were AlpInvest Partners, AXA Private Equity, AIG Investments, Goldman Sachs Private Equity Group and Pantheon Ventures.