This study examined whether nonclinical obsessions and nonclinical compulsions relate differently to cognitive and mood factors such as responsibility, perfectionism, trait anxiety and depressed mood. Two hundred and three nonclinical undergraduate psychology students (70.4% females, 29.6% males, mean age = 18.7, SD = 1.1) completed questionnaires. After controlling for the relationship between obsessions and compulsions, obsessions were found to relate significantly more strongly to depressed mood, trait anxiety, socially prescribed perfectionism and responsibility than compulsions. Conversely, compulsions were found to relate more strongly to self-oriented perfectionism than obsessions. These results were interpreted as providing support for the notion that obsessive-compulsive disorder (OCD) is maintained by a conflicted mental representation of the self and the world. Obsessions were interpreted as reflecting an overdeveloped vigilance for threat, responsibility and need for social approval. Compulsions were interpreted as emanating from the belief that the self is self-sufficient and resourceful, and that the world is ordered and systematic. Implications for the treatment of OCD were discussed.