Sulka, spoken along Wide Bay in the East New Britain province of Papua New Guinea, is known as an isolate Papuan language. In the area where Austronesian and Papuan languages have been in contact over the last three-and-a-half millennia, this is one of a number of languages that are difficult to classify. The question is often raised whether a language is basically Papuan or Austronesian, with some kind of borrowing from the other linguistic stock. In this paper it is argued that clusters of features can shed light on the genealogical or contact history of a language. On this basis, Sulka can be typified as having ancient Papuan (non-Austronesian) roots, but with a number of morphosyntactic constructions and some vocabulary that are associated with the Oceanic branch of Austronesian, in particular the languages of the St. George linkage. It is hypothesized that some Western Oceanic innovations may actually have originated in Papuan languages such as Sulka.