Using methods from anthropology and cognitive psychology, this study investigated the relationship between clinicians’ folk taxonomies of mental disorder and the Diagnostic and Statistical Manual of Mental Disorders (DSM). Expert and novice psychologists were given sixty-seven DSM-IV diagnoses, asked to discard unfamiliar diagnoses, put the remaining diagnoses into groups that had “similar treatments” using hierarchical (making more inclusive and less inclusive groups) and dimensional (placing groups in a two-dimensional space) methodologies, and give names to the groups in their taxonomies. Clinicians were familiar with a substantially smaller number of diagnoses than are in the DSM. Cultural consensus analysis and follow-up residual agreement analysis revealed similarities across clinicians’ folk taxonomies. Correlations between folk taxonomies and the DSM were moderate. Cluster analysis showed that clinicians preserved DSM higher order categories (e.g., mood disorders) but not the Axis I–Axis II distinction. This study suggests important differences between the way clinicians conceptualize mental disorders and the organization of the DSM-IV.