William Krehm (November 23, 1913 – April 19, 2019) was a Canadian author, journalist, political activist and real estate developer. He was a prominent Trotskyist activist in the 1930s and went to Spain where he participated in the Spanish Civil War. In the 1980s he co-founded the Committee on Monetary and Economic Reform (COMER) in the 1980s and continued as the group's principal leader until his death. He died in April 2019 at the age of 105.