In this Open Forum the Committee on Psychopathology within the Group for the Advancement of Psychiatry (GAP) strongly encourages clinicians and health systems to implement standardized assessments of patients' outcomes for mental disorders, particularly disorders such as depression. The GAP committee describes how calls for the regular use of standardized scales in clinical settings naturally follow from the development and dissemination of treatment guidelines. It discusses the challenges involved in implementing routine outcome measures in clinical settings and explains why the advantages of measurement-based care make addressing these challenges worthwhile. Finally, the committee makes practical suggestions for clinicians and systems attempting to implement routine outcome measures in their clinics.