Gary Sidney Ryan (1916–2007) was an eminent philatelist who specialised in the stamps and postal history of Hungary and later in revenue stamps. Ryan was awarded the Crawford Medal of the Royal Philatelic Society London in 1988 for his work on the cancellations of Hungarian Post Offices on the first stamps of Hungary and he signed the Roll of Distinguished Philatelists in 1980. His philatelic writing won him a rarely awarded Grand Prix award for Literature at Frankfurt in 1989. Ryan's profession as a lawyer helped him obtain revenue stamps used on documents with which to expand his collection.