A contrast has emerged in recent debates on fashion in modern industrialized societies between the integrationist approach and what I propose to call the conflict approach. Both begin from the classic theory of fashion, propounded by Veblen and Simmel, and based on concepts of elite and the `trickle-down' effect. The first approach denies and the second approach asserts the permanent validity of this theory for the contemporary world. In this article I argue that these theories are not mutually exclusive, but rather complementary, because they help to understand and explain different fashion processes: fads or crazes, market fashion - that is, consumption spreading processes driven by the system of production - and structural fashion, that is innovations in social habits marked by the presence of an innovative elite and of the trickle-down effect.