There is clear overlap in the clinical symptoms of obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). As a result, OCD (with or without tics) and TS (with or without obsessive-compulsive symptoms [OCS]) have been conceptualized to form a disorder spectrum—an overlapping set of phenotypes reflecting presumed commonality at the level of the underlying genetics and neuropathology. We identified the characteristics of a research sample of patients with OCD or TS, based on information obtained in semistructured clinical interviews, to examine the similarities and differences in the clinical symptoms across this spectrum. This sample conformed to known age-of-onset and sex distribution patterns for OCD and TS. Previously reported patterns of predominant aggressive and sexual obsessions and touching compulsions were observed in subjects with tic-related OCD, compared with non—tic-related OCD (ie, OCD alone). The majority of patients with tic-related OCD experienced horrifically violent obsessions that were less common in OCD alone and much less common in TS. Nonetheless, symptomatic and functional impairment in TS subjects was clearly related to the intensity of their OCS. The specific obsessions and compulsions associated with clinical impairment in TS differed from those associated with impairment in OCD. These results suggest that, despite the many overlapping dimensions of these disorders, the symptoms and associated impairment in “pure” OCD, tic-related OCD, and TS do not form a simple continuous spectrum.