Synopsis Sartre, a man of multifaceted personality-philosopher, critique, novelist and dramatist-is one of the most influential men of the century. This monograph attempts at an outdrive survey to elucidate the important issues central to Sartre’s philosophy. The major focus is on the analysis of the nature of Man, Society and Freedom and their relation in his earlier and later work i.e. Being and Nothingness and Critique of Dialectical Reason respectively. The two masterpiece represent two distinct dimensions of his thought, the former concerning the ontological study of man and the latter dealing with man’s role in society as a maker of his own history and consequently maker of the history of mankind. The distinction evokes many debates among critics regarding unity and continuity of Sartre’s thought. Here apart from the study of the nature of Sartre’s earlier and later works related to his concepts of man, society and freedom, this work tries to show whether there is any continuity between these two phases in his philosophy.