An empirically based, clinically usable approach to cross-informant integration in clinical assessment is needed. Although the importance of this ongoing issue is becoming increasingly recognized, little in the way of solid recommendations is currently provided to researchers and clinicians seeking to incorporate multiple informant reports in diagnosis of child psychopathology. The issue is timely because recent developments have created new opportunities for improved handling of this problem. For example, advanced theories of psychopathology and normal and abnormal child development provide theoretical guidance for how integration of multiple informants should be handled for specific disorders and at particular ages. In addition, more sophisticated data analytic approaches are now available, including advanced latent variable models, which allow for complex measurement approaches with consideration of measurement invariance.