This article analyzes the diachronic rise of complex discourse markers, that is, markers consisting of more than one word. First, a taxonomy of four types of complex markers is proposed. Two of these types lend themselves to a specific diachronic analysis. Second, two complex French markers are analyzed in detail : bon ben and enfin bref. The diachronic rise of these two markers confirm the hypothesis that complex markers arise in a process of “over-use” of a given sequence of source words. These sequences are over-used in response to a functional need for these particular combinations of words in structuring discourse and interactions, regardless of whether the combinations of words are syntactic phrases or just a series of adjacent markers in discourse.