He began his first serious work related to civil rights when he was appointed to the PCUSA's Board of Christian Education's Department of Social Education and Action. He became an associate executive on the board, holding the position for five years. Wilmore then became a member of the faculty of Pittsburgh Theological Seminary, where he worked from 1959 to 1963 as assistant professor of social ethics. In 1963, when the 175th General Assembly of the UPCUSA convened, it created the Commission on Religion and Race, naming Wilmore as its executive director. During his time as executive director, Wilmore oversaw several racial justice initiatives, organized protests, and trained ministers to participate in boycotts. He served as executive director from 1962 until 1972.