In this article, we focus on the morphosyntactic and semantic properties of constructions involving the well-known syncretic non-active and/or reflexive morphology (depending on the language). We show that if we treat this special morphology as a property of Voice, non-active / reflexive constructions fit into a consistent, independently attested pattern of cross-linguistic variation in properties of functional heads, allowing us to derive the syntactically different constructions (reflexive, anticausative, middle, passive) exhibiting non-active/reflexive morphology in a unified manner. We argue for the general cross-linguistic schema [VoiceP Voice … [VP V IA ]], with Voice licensing (via Agree) the Internal Argument (IA) or the PP in all cases but in differing ways.