In 1987, Kohlberg founded Kohlberg & Co., a leading U.S. private equity firm where he is now a special limited partner. He is the co-founder of Kohlberg Kravis Roberts & Co., established in 1976, and remains a limited partner in that private equity firm.

Kohlberg graduated from Swarthmore College in 1946 with a B.A. in economics. He later earned an MBA from Harvard and an LL.B. from Columbia University. Swarthmore awarded him an honorary doctor of laws degree in 1986. He has served Swarthmore as a Board Member from 1972 to 1983 and again from 1989 to 1994.

He is involved in many civic and charitable organizations including The Kohlberg Foundation, The Campaign Reform Project, The Campaign for a New GI Bill, The Initiative to Protect Student Veterans, and The Cabbage Hill Farm and Foundation Inc. He established The Philip Evans Scholarship Foundation in honor of Phil Evans, his college roommate.

He is a past Chairman of the Board of The Salk Institute for Biological Studies.

He is married to Nancy Seiffer Kohlberg and has four children.