The American Topical Association (ATA) is a US-based philatelic society and the largest organization devoted to topical stamp collecting. It was established in 1949, and currently serves members in over 90 countries.[1] ATA publishes Topical Time, its bimonthly journal.[2] It also publishes various handbooks dealing with various topics as well as maintaining checklists of philatelic material organized by topics. The organization also runs the National Topical Stamp Show, its annual convention, as well as supporting 49 study units on various topics and 32 local chapters.[2]