The concept of role overlap between occupational therapy and physiotherapy has been the subject of debate for at least three decades. Stroke rehabilitation is an area where role overlap between occupational therapists and physiotherapists occurs. This article reports an exploratory study carried out with nine physiotherapists and nine occupational therapists working in a variety of in-patient stroke rehabilitation settings. Analysis of qualitative data collected through semi-structured interviews revealed that the majority of the participants recognised the existence of role overlap as inevitable within collaborative health care and felt it was of benefit to patients. However, it appeared that the concept was also perceived as a challenge to role security by many when considered from a professional perspective. Acceptance of role overlap depended upon the extent to which it occurred in the particular setting. Generic therapy was seen as an extreme form of overlap and regarded as an undesirable progression by most participants. The main strategy used to challenge this development was to emphasise professional uniqueness through role delineation. However, this strategy was found to be weak in the context of increasing demands for collaboration at a policy level.