[4] His first comic-book story, the six-page backup feature "The Visit", appeared in First Comics' Grimjack #57 (cover-dated April 1989).

[5] About Comics would go on to publish properties such as The Weasel Patrol, The Factor, Licensable BearTM, and The Liberty Project.

[6][7] In 2004, he founded the annual 24 Hour Comics Day challenge to cartoonists to produce a 24-page comic book,[7] based on a concept previously conceived by Scott McCloud and Steve Bissette in 1990.

[9] In November 2016, Gertler's company About Comics began publishing facsimile editions of The Negro Motorist Green-Book guides, originally published by Victor Hugo Green and his wife Alma Green from the 1930s to the 1960s to help African-Americans travel safely in a segregated U.S.[10][11] Gertler's 2010 The Peanuts Collection received positive reviews in USA Today[12] and elsewhere.

The Chicago Sun-Times described it as a "slipcovered museum collection" filled with "treasures",[13] and the Christian Science Monitor described it as "a gold mine of Peanuts memorabilia and removable inserts".