Duncan Long has been painting for several decades, and his illustrations have appeared in magazines and books from HarperCollins, PS Publishing, Pocket Books, Asimov's Science Fiction Magazine, Enslow Publishers, The National Examiner, and many other presses.

Long was chosen as a featured artist for the Collaborative Summer Library Program in 2013 and named one of the "best graphic artists in the entire world" by talk-show host Victor Thorn. In addition to working as an artist, Long has also written a number of fiction and non-fiction books and currently serves as the art director for Amazing Stories Magazine.