Leonard was born in Fall River, Massachusetts on 26 December 1941. After serving in the U.S. Army from 1960 - 1963, he studied at the Swain School of Design in New Bedford, Massachusetts, the Skohegan School of Painting & Sculpture in Maine, & at the Maryland Institute College of Art in Baltimore, Maryland, B.F.A., M.F.A., 1970.
Leonard has taught at the Maryland Institute, Bristol Community College, Bennington College, New York University, & The Art Students League.
Respectable homes have been found for all of Leonard's pictures by OK Harris Works of Art, in New York City since 1975.
In April, 2003 Leonard was the recipient of a grant from the Pollock Krasner Foundation.
His first marriage produced two daughters, now grown with children of their own. A New York City resident for twenty years, he now lives & works, somewhat reclusively, in a 19th century farmhouse in upstate New York with his wife & teenage daughter.