Stanisław Lem (Polish pronunciation: ( listen); 12 September 1921 – 27 March 2006) was a Polish science fiction, philosophical and satirical writer. His books have been translated into 41 languages and have sold over 27 million copies. He is perhaps best known as the author of Solaris, which has twice been made into a feature film. In 1976, Theodore Sturgeon claimed that Lem was the most widely read science-fiction writer in the world.

His works explore philosophical themes; speculation on technology, the nature of intelligence, the impossibility of mutual communication and understanding, despair about human limitations and humankind's place in the universe. They are sometimes presented as fiction, but others are in the form of essays or philosophical books. Translations of his works are difficult and multiple translated versions of his works exist.