Starting with the Crisis on Earth story, the Justice League of America meets the Justice Society of America! The teams have to team up if they want to defeat the Crime Champions and they ll even have to switch Earths?! Will the teams solve the Crisis of Two Worlds? The JLA will team up with the JSA in more adventures and even face off against enemies, like the Crime Syndicate, on their own! Collects Justice League of America #21-22, Justice League of America #29-30, Justice League of America #37-38, Justice League of America #46-47, Justice League of America #55-56, Justice League of America #64-65, Justice League of America #73-74, Justice League of America #76, Justice League of America #82-83, and Limited Collectors Edition #46.