This volume is a collection of articles on clitic doubling, a phenomenon that has preoccupied generative linguists since the 1980s, when its theoretical importance was noted. Clitic doubling is prevalent in the Balkan languages. However, generative studies initially dealt with its properties in Romance languages, with the Balkan patterns coming increasingly into focus. Since the mid-nineties, these patterns presented a variety of challenges to the generalisations reached on the basis of Romance, while also raising new research questions. The volume deals among other things with the following aspects of the phenomenon: its extension within and outside the Balkan Sprachbund and the observed variation; its realizational possibilities and the constraints on the status of the doubled DP (direct or indirect object, pronominal or non-pronominal); its semantics (definite, specific, presupposed, neither) and pragmatics (topic or not, D-linked or not); its temporal and locational genesis; the relationship between the clitic and its associate.