Yesod HaTeshuvah – “The Foundation of Repentance” in English – is a short work on repentance attributed to 13th-century scholar Rabbeinu Yonah Gerondi. It serves as a practical guide to starting the process of repentance, instructing the reader regarding which thoughts to focus on and which to avoid, providing the text of a prayer to recite when embarking on a process of repentance, and describing how to structure one’s day intentionally so as to foster change.