Southeast Asia is home to members of five language families, namely Austro-Asiatic, Sino-Tibetan, Tai-Kadai, Hmong-Mien, and Austronesian. Hundreds of years of close contact have inevitably led to a large number of cases of convergence on all levels of the linguistic systems. Languages have not only borrowed lexical items from each other, they also copied or replicated semantic and syntactic structures. As some languages have a documented history of over a thousand years, some evidence of the direction of influence and the source of diffusion can be gained from historical comparisons. In spite of this, and in spite of the fact that a number of languages of the region are rather well known, much is still needed in terms of typological comparison. Especially the Austroasiatic languages are still not very well described and a general typological overview is still lacking. The same is true for the Tai-Kadai languages. Most current work covering more than one language concentrates on historical lexical comparison and language classification, with syntax being neglected by most linguists active in the area. My ongoing research especially in Austro-Asiatic, but also Tai-Kadai and Tibeto-Burman languages, focuses on syntactic typology, with the long term aim of establishing typological profiles of these langauges.