In recent years, the typological and geographic range of languages subjected to sociophonetic study has been expanding, though until now Australian Aboriginal languages have been absent from this subdiscipline. This first sociophonetic study of an Australian language, Murrinh Patha, shows a type of consonant lenition that is notably distinct from the better known examples in Standard Average European languages, effecting /p/ and /k/ primarily in the onset of stressed, usually word-initial syllables. Young men lenite more frequently than older men do, and paternal heritage from the neighboring Marri language group also predicts more frequent lenition. The latter influence may be the result of intense language contact brought about by recent settlement of diverse language groups at the Catholic Mission of Port Keats.