This paper presents state-of-the-art models addressing issues related to coordination of treatment and evaluation activities, and integration of clinical, performance, and evaluation information. Specifically, it summarizes the background, methods, and tools needed for substance treatment professionals to reliably assess client levels of functioning (LOF). LOF measures capture important client perspectives and add to the validity of evaluations of treatment effectiveness. These measures can also serve as an important basis for the development of quality care indicators and treatment provider performance measures. Appendix A is "Integrated Evaluation Methods Package: A Guide for Substance Abuse Treatment Knowledge-Generating Activities--Executive Summary"; Appendix B is"Psychometric Properties of LOF Instruments Reviewed"; Appendix C is "Contact and Public Use Information"; Appendix D is "Instrument Domains"; Appendix E is "Annotated Bibliography"; and Appendix F is "References for Each Instrument." (Contains 7 tables and 128 references.) (MKA)