Popular science-fiction writers, the Strugatsky brothers have used the genre since the 1960s to comment on contemporary society, at times provoking major controversy. It's Hard to Be a God (1964) is a dysutopia with commentary on historical theories. The Snail on the Slope (1966--68) features a KGB-like organization and an extraordinarily oppressive atmosphere. Pre-glasnost, glasnost, some of the Strugatskys' major works had to be circulated in samizdat, but the brothers' situation is now dramatically better.