In this chapter we explore the interrelated phenomena of conventionalization and conventions. We argue that the essence of convention is to facilitate meaning making in interaction, while conventionalization refers to the process through which conventions come into existence. We investigate the pragmatic complexity surrounding convention and conventionalization by arguing that (1) conventionalization is a matter of degree; (2) conventions and conventionalization are particularly prominent in intercultural interactions; and (3) language and socialisation are highly relevant to conventionalization. We also investigate facets of language use with complex implications for convention and practice, and we provide various interactional examples to illustrate these facets.