In 2011 Allen & Overy senior partner David Morley convened a meeting of senior partners from several top U.K. law firms to propose a novel social mobility initiative. Morley—who comes from a working-class background, the first graduate of his state school to attend an elite university—wanted to address the U.K. legal profession's long-running problems with socioeconomic diversity. His idea: 2,500 law firm internships for students from less-privileged backgrounds by 2015. A few months later, with the support of 23 firms, PRIME was launched.

Member firms commit to providing high school–age interns with a minimum of 30 hours of training to develop business and personal skills. The firms also provide financial assistance to the students during their internship and maintain contact with them once it ends. According to the National Foundation of Educational Research, PRIME exceeded its targets by creating over 750 placements in its first 12 months. About 80 law firms now participate, with the London offices of several Am Law 100 firms—including Baker & McKenzie, Mayer Brown, and Reed Smith—among the new members. The ultimate goal is to expand the program nationwide.

"Lots of people pay lip service to social mobility, but David is someone who is truly passionate about it," says James Turner, partnerships director at educational charity The Sutton Trust and a member of the PRIME board. "The reason [that] PRIME has been so successful is that it's a fundamentally good idea, but David has been instrumental in bringing firms to the table."