Introduction The major objective of the present research work is to present a comprehensive and an objective study of the major teachings and the practices involved in these two systems: Early Buddhism and Patabjala Yoga. This is done in such a way as to give the reader an in-depth understanding of the most fundamental and salient aspects of the two systems. To do this a vast amount of data is collected, and aligned to make this whole picture clear and comprehensive. An attempt has been made to place both these systems in their proper contexts, tracing their early beginnings and antecedent developments. There are a number of well authenticated books by reputed authors devoting considerable space to both these systems. In these the two areas are treated as components of a wider area of study, and the focus is, therefore, rather general. There is no comparative study of these two systems, when critically examining the similarities and differences. Hence, a need was felt about such a comparative study. This research is to fill this need. This is a comparative study of Early Buddhism and Patabjala Yoga. However, it is based on a textual study. The Sutta Pitaka has been used as the primary source for Buddhism, and Yogasutra for Patabjala yoga. The commentaries of texts belonging to both systems have also been used as and when necessary. The approach adopted is critical. However,