Attributions regarding the nature, cause, and best treatment of mental health problems were examined in a total of 563 adults with serious mental illness from four ethnocultural groups, 185 family members, and 43 mental health practitioners. Attributions agreed in many areas, such as stress as a cause, and medical intervention and counseling as best treatment. Differences were found between the practitioner and other groups in attributions regarding the senses in the nature of mental illness, and in drugs and alcohol as a cause. The role of ethnicity was examined and treatment implications discussed.