This paper reports the finding of a study that explores the influence of language contact on the interpretations of Australian Sign Language (Auslan)-English interpreters and compares it with the influence of language contact on deaf Australian producing text in Auslan. Inspired by the work of Davis (1990, 2003) on American Sign Language (ASL)/English interpreters, this study presents first of all the analysis of data collected from two Auslan/English interpreters, and their interpretation of university lectures from spoken English into Auslan. The key features discussed are the use of fingerspelling and mouthing in the context of interlingual transference and interlingual interference. Referring to language contact phenomena between signed and spoken languages, as discussed by Lucas and Valli (1992) and Davis (1990, 2003), the paper discusses the sign language output of Auslan-English interpreters in relation to the influence of language contact on the Australian Deaf community. In addition, the paper presents analysis of data collected from two deaf Australians presenting university lectures in Auslan. The linguistic features identified are compared with those of the interpreters.