Robert Bonfils started his illustration career in Chicago in the mid 1950s, doing various commercial art assignments such as advertisements, decorations, illustrations and magazine, record and book covers. He was then hired by Hamling Organization as art director. He moved to San Diego where Hamling was located and began to produce paperback book covers exclusively for them. The titles were published under a variety of imprints within the Hamling group, such as Nighstand Books, Leisure Books, Adult Books, Candid Readers, Companion Books and others, commonly known today as Greenleaf Classics. Bonfils retired from doing cover art in the mid 1970s. The cover art on Greenleaf Books was never signed so the identity of the artist who did the covers was unknown until the mid eighties when information surfaced among specialty book collectors that the artist was named Bonfils. In 2002, Bob was reunited with Earl Kemp, an editor at the Hamling Organization. Most of the original art for the Greenleaf covers has been lost, although a few pieces have survived.