Behind every private-equity buyout is a cadre of lawyers. Behind some of the biggest buyouts was Dick Beattie.

Beattie, who ended his career as senior chairman of law firm Simpson Thacher & Bartlett, was among the first attorneys to recognize private equity’s potential. He rode the industry’s explosive growth, becoming one of the country’s top mergers-and-acquisitions lawyers and shaping Simpson Thacher into a private-equity powerhouse.