This chapter presents a preliminary typology of interjections in Australia, based on a balanced sample of 37 languages. We first discuss the classification of interjections into classes, then specific semantic profiles, as well as resemblances in forms where applicable. Most of the interjections in our data fit within one of the three classes identified by Ameka (1992)—conative, phatic, and expressive. Yet, two additional small classes, labelled ‘constative’ and ‘social’, are needed to reach a satisfying classification. Of the major classes, conative interjections are the most frequently reported; and among them, attention-seekers are the most frequent semantic profile. Phatic interjections are less consistently described, except for the very widespread ‘yes’ and ‘no’. Among expressive interjections, pain, surprise and compassion are the most common types, and pain and surprise present remarkable resemblances in form. Further research is needed to assess whether these observations are specific to Australia, or reflect universal trends.