The Firm: Proskauer Rose comes recommended for its work in the private equity sector, advising clients on matters including fund formation, M&A and other transactions. Major clients of the group include Adams Street Partners, Lexington Partners and Cambridge Associates.

Sources Say: "They are very responsive and really understand our business from all sides."

Key Individuals: Arnold May is a "highly skilled and thoughtful tax lawyer" who can "speak the businessperson's language and take the business perspective," clients say. He focuses on advising private equity fund managers on fund formation, internal organization and investment matters.

Scott Jones is "incredibly technical and very talented, but also highly reasonable and can take a practical approach to solving problems." Of late he advised Bessemer Venture Partners on its latest capital raising project, which had a value of $1.6 billion.