The doctoral research that led to this book was based on the sociology practised and taught by Florestan Fernandes and described by his readers as 'Critical Sociology'. By retrieving the academic production of Florestan Fernandes, his commentators and those who had him as an object or subject of study, one can see with significant clarity the elements that suggest a lively dialectical construction between the individual and society in the academic space. Thus, by appropriating the concept of criticism and its application in Florestan Fernandes' theoretical work and empirical research, as well as in the analysis of the literature that deals with its reception, the conclusion reached is that the term "criticism" can be observed especially in Florestan Fernandes' scientifically rigorous attitude towards both the object of knowledge and the methods of the sociological discipline. Following his example, it is proposed that in the sociologist's craft many misconceptions surrounding the use of the concept of criticism could be avoided if the theoretical and methodological basis of Florestan Fernandes' work were observed and taken into account.