The Justice Society of America, or JSA, is a DC Comics superhero group, the first team of superheroes in comic book history. Unlike subsequent "all-star" teams, the JSA was limited to heroes not already featured in their own titles because the publisher wanted to expose their lesser known characters. Hence, Superman and Batman were only honorary members and Flash and Green Lantern's early tenures were brief, ending when each character was awarded his own book. However, a 1944 change in policy allowed them back into the group. Other popular members were Hawkman, the Spectre, Hourman, Doctor Fate and the Atom.