Greg's work has appeared in numerous publications including Rolling Stone, The New York Times, Time Magazine, The Atlantic, Mother Jones, The Wall Street Journal, and The New Yorker. Corporate and publishing clients have included Charles Schwab, Target, Einstein Bros. Bagels, Merry Down Cider (UK), Dweck Properties, Purina, Chase Bank, Simon & Schuster, Candlewick Press, and Random House. He is the co-author and illustrator of A Sidecar Named Desire: Great Writers and the Booze That Stirred Them (Harper Collins 2019).
He has been featured in Taschen's Illustration Now!, Luerzer's Archive's 200 Best Illustrators Worldwide, and was profiled in 3x3 Magazine (Issue 8). A consistent presence in such awards annuals as American Illustration and Communication Arts, he is also the recipient of three silver medals from the New York Society of Illustrators.