The present book contains a series of lectures delivered at the Ecole Pratique des Hautes Etudes (Paris) in March 2015 and at the Savitribai Phule Pune University (Pune) in October and November 2015. This volume grew out of efforts to teach the textual criticism of Sanskrit works in theory and practice. It covers the general theory of textual criticism, its history and practice in Sanskrit studies, and tries to offer concrete examples of newly edited texts in order to show that Sanskrit editing is not so much a specialist knowledge, but a basic skill for Sanskrit readers. 'To edit or not to edit' will appeal to specialists with interests in fields such as Sanskrit philology and textual criticism, history of Indology, old, medieval, and modern Sanskrit texts from Kashmir, as well as Indo-Persian studis.