Prelude to Foundation is a Locus Award nominated 1988 novel written by Isaac Asimov. It is one of two prequels to the Foundation series. For the first time, Asimov chronicles the fictional life of Hari Seldon, the man who invented psychohistory and the intellectual hero of the series.

The story takes place on Trantor during the reign of Emperor Cleon I. It starts with Hari's presentation of a paper at a mathematics convention detailing how practical use of psychohistory might theoretically be possible. The Emperor of the Galactic Empire learns of this and wants to use Hari for political gain. After an interview with Hari, however, Cleon concludes that Hari is of no use to the Empire.

Hari then meets reporter Chetter Hummin, who convinces him that Cleon's first minister Eto Demerzel is attempting to capture him, and that it is therefore imperative for Hari to escape and to try to make psychohistory practical. Thus, Hari goes on his "Flight" and is introduced to Dors Venabili by Hummin.

Hari and Dors narrowly evade capture at Streeling University, following which the pair move to Mycogen. Hari and Dors are welcomed to Mycogen by Sunmaster Fourteen, the leader of Mycogen. Determined to work out his psychohistory with the knowledge that the Mycogenians supposedly possess, Hari decides to speak to a Mycogenian alone about history. He manages this by convincing Raindrop Forty-three to show him the prized Mycogenian microfarms, a prized source of food for the aristocracy and Mycogenians alike.