It has been suggested, on the basis of neuroanatomical and behavioural data, that olfactory discrimination in the rat provides privileged access to higher cognitive processes, involves the acquisition of a learning-set and, importantly, can be used to model human hippocampal function and dysfunction. In this article, Ian C. Reid and Richard G. M. Morris question the assumptions upon which these claims have been based and criticize the application of odour discrimination learning in the rat to the study of human memory.