The Past Through Tomorrow is a collection of science fiction stories by American writer Robert A. Heinlein, first published in 1967, all part of his Future History.

Most of the stories are parts of a larger storyline about the future rapid collapse of sanity in the United States, followed by a theocratic dictatorship, a revolution, and the establishment of a free society that does not save the pseudo-immortal Lazarus Long and his Howard Families from fleeing Earth for their lives. Most editions of the collection include a timeline showing the chronology of the stories (including stories never written, such as "The Stone Pillow", which was to occur during the period of the theocracy), times of birth and death of the significant characters, and commentary by Heinlein.

The specific short stories included vary with the edition, but typically include:

• "Life-Line", 1939; a month before "Misfit"
• "Misfit", 1939
• "The Roads Must Roll", 1940
• "Requiem", 1940
• "'If This Goes On—'", 1940
• "Coventry", 1940
• "Blowups Happen", 1940
• "Universe", 1941
• "Methuselah's Children", 1941; extended and published as a novel, 1958
• "Logic of Empire", 1941
• "'—We Also Walk Dogs'", 1941
• "Space Jockey", 1947
• "'It's Great to Be Back!'", 1947
• "The Green Hills of Earth", 1947
• "Ordeal in Space", 1948
• "The Long Watch", 1948
• "Gentlemen, Be Seated!", 1948
• "The Black Pits of Luna", 1948
• "Delilah and the Space Rigger", 1949
• "The Man Who Sold the Moon", 1950
• "The Menace from Earth", 1957
• "Searchlight", 1962

The 1975 and 1986 paperback editions, and likewise the 1967 hardback, are missing the story "Universe" (Orphans of the Sky).