The paper examines the distinction between realis- and irrealis-marking complementizers (ka vs. da in the Prekmurje (Pannonian) dialect of Slovene and compares the phenomenon to the same distinction observed in Balkan Sprachbund languages (Albanian, Bulgarian, Modem Greek, Macedonian, Romani, Romanian). Though the phenomenon is indeed synchronically parallel, historically the distinction in Prekmnrje Slovene arose as a result of retentions on the periphery (partially shared with the Carinthian dialects) and not as a result of (erstwhile) contact with languages of the Balkan Sprachbund