Background: The evidence supporting the application of Weiner's motivational model of helping to the behaviour of carers' of people with intellectual disabilities and challenging behaviour is inconsistent. One suggested reason for this is that many studies use stimuli that might generate different responses from those to actual instances of behaviour of real people. Method: Sixty-two paid carers of people with intellectual disabilities reported attributions, emotions and intended behavioural responses to behaviour presented by an unnamed person and the same behaviour presented by a named and known person. They also completed a scale of behavioural knowledge. Results: Carers make more internal and global attributions and identify themselves as less optimistic in response to vignettes relating to named and known people than those relating to unnamed people. However, data from both unnamed and named vignettes are consistent in supporting Weiner's motivational model of helping in demonstrating a mediated model for controllability, anger and helping intention. Conclusions: Unnamed vignettes may underestimate the intensity of carers' responses to challenging behaviour; however, this study does not provide evidence that there are qualitative differences in the interrelationships between variables in data sets obtained from unnamed and named vignettes.