Bill received a Ph.D. in Christian Social Ethics from Boston University. In 1970 he became the long-time head of the Church Council of Greater Seattle where he fostered social activism, ecumenism and the ethics of Jesus.

After his retirement in 1990, Dr. Cate helped found the Institute for Ecumenical Theological Studies at Seattle University, realizing a lifelong dream for what he called a "first class theological school" in the Pacific Northwest.

He died January 13, 2016.