John Greco began his art training in the early 1970s, studying printmaking with Glen Brunken, Will Petersen, and Dan Rohn. He graduated with a Bachelor of Fine Art from Slippery Rock University, and received his Master of Fine Arts in Printmaking from Kent State University. He has taught courses in art and photography at the American Intercontinental University, Kent State University, Slippery Rock University, University of Southern Californian. Currently he teaches printmaking and drawing classes at Santa Monica College.

In 1984, Greco established Josephine Press, a printmaking studio in Santa Monica, with the intention of providing a center for artists to explore the creative potentials of printmaking and to publish editions of fine art.

In 1989, he opened Christopher John Gallery, in conjunction with Josephine Press, to represent and exhibit the works of innovative artists and printmakers. John has collaborated with more than 500 artists from around the world and has taught numerous printmaking workshops throughout the United States and Europe. Among the many artists with whom he has collaborated are John Cage, Meg Cranston, Muramasa Kudo, Michael McMillen, Joseph Piasentin, Raymond Pettibon, Edgar Heap of Birds, Nancy Riegelman, Arturo Segundo, Paul Soldner, Peter Milton, Bob Branaman, Martin Mull and Stas Orlavski. He has exhibited extensively at home and abroad, and is represented in many public and private collections.