This chapter focuses on the resistance movements provoked by the European integration within the European Parliament. More particularly, it addresses 3 questions: How is it possible to describe Eurosceptic MEPs? Beyond their political affiliations, are there any converging points of reference in their way of thinking, their rhetoric or their attitudes? From a sociological perspective, how can we define the typical role of the Eurosceptic MEP? The chapter proposes a definition of euroscepticism along two axis and four ideal-types of parliamentary roles for Eurosceptic MEPs.