Tutors trained in applied behaviour analysis (n = 16) and mainstream school teachers (n = 16) were exposed to an Implicit Relational Assessment Procedure (IRAP) designed to assess implicit attitudes towards individuals with autism versus normally developing individuals. Participants also completed a range of explicit measures, including measures of professional burnout and psychopathology. All participants produced more negative biases towards children with autism compared to children who were normally developing. Increased negativity towards autism on the IRAP predicted similar attitudes on some of the explicit measures and also correlated with increased levels of self-reported psychopathology and professional burnout for the tutors working with children with autism. Results suggest that implicit measures of attitudes may provide a marker for professional burnout. (Contains 3 tables and 2 figures.)