On August 20, 2019, Wilson Sonsini announced that the firm has achieved Mansfield Plus Certification, after having participated in the Mansfield 2.0 pilot program for law firms, signifying that at least 30 percent of the firm's appointments to leadership roles, promotions to equity partner, senior-level lateral hires, and inclusion in formal business pitches were women attorneys, attorneys of color, and LGBTQ+ attorneys.

The Mansfield Rule, named after Arabella Mansfield, the first woman admitted to practice law in the United States, was one of the winning ideas from the 2016 Women in Law Hackathon, a pitch competition created by the Diversity Lab in collaboration with Stanford Law School and Bloomberg Law. The first Mansfield Rule pilot program was launched in 2017, and in 2018, more than 65 law firms, including Wilson Sonsini, signed on to participate in the Mansfield 2.0 pilot, which recently ended in July 2019.

Wilson Sonsini is participating in the Mansfield 3.0 pilot, which adds attorneys living with disabilities as a tracked category. Additional information about the ongoing program can be found here.