A different kind of book! It is the work of a medical man by profession, an Indologist by choice, a Sanskrit scholar of depth, an academician of repute, a researcher of commitment and a guide for research in psychology. This book is all about Patanjali Yoga-sutras with the Upanishads in the background. It is a study of them for the purpose of understanding the instruction of Patanjali directly from the words used by him. There is no display of erudition for its own sake. Every word of each sutra is analyzed for what it means. As the author points out, "Although the texts concerned are themselves very clear about the topics they deal with, an objective study of their contexts always appeared smothered from adventitious pressures to prove or disprove something insistently held by the varying traditions belonging to the different ages in history. Never were the texts studied in terms of the contexts provided by themselves". In this way, this book is different from the other expositions on the subject and offers the impetus for further research on similar lines.