FIRST, SOME OF THE KEY PROPOSITIONS IN I-LEVEL THEORY ARE REVIEWED, AS IS THE TOPOLOGY DERIVED FROM THE THEORY. THEN AN INVESTIGATION IS UNDERTAKEN OF THE RELATIONSHIP BETWEEN THE THEORY AND EARLIER STUDIES CLAIMED TO BE SUPPORTIVE OF IT. NEXT, THREE REHABILITATION PROJECTS THAT UTILIZED I-LEVELS ARE EVALUATED. THESE INCLUDED THE CAMP ELLIOT STUDY, CALIFORNIA'S COMMUNITY TREATMENT PROJECT, AND THE PRESTON STUDY. THIS IS FOLLOWED BY AN EXAMINATION OF SOME RESEARCH PROBLEMS THAT MIGHT EXPLAIN LIMITED SUCCESS IN I-LEVEL PROJECTS. FINALLY, THERE IS A SUMMARY THAT INCLUDES ADDITIONAL CONSIDERATIONS FOR POLICYMAKERS. IT IS CONCLUDED THAT VALID QUESTIONS MAY BE RAISED ABOUT THE EXTENT TO WHICH I-LEVEL THEORY BENEFITED FROM EARLIER STUDIES. HOWEVER, THE THREE I-LEVEL REHABILITATION PROJECTS DISCUSSED IN THIS STUDY PROVIDE EVIDENCE FAVORABLE TO THE IMPORTANT HYPOTHESIS OF INTERACTION BETWEEN I-LEVEL AND TREATMENT ENVIRONMENT, ALTHOUGH THE APPARENT EXPECTATION OF GREATER REHABILITATION SUCCESS FOR ALL SUBJECTS IN THE EXPERIMENTAL GROUP HAS NOT ENCOURAGED ENTHUSIASM FOR THE CALIFORNIA COMMUNITY TREATMENT PROJECT IN WHICH ONLY THOSE DEEMED NEUROTICS SHOW CLEAR BENEFIT FROM DIFFERENTIAL TREATMENT IN THE COMMUNITY. FURTHER, IT IS CONCLUDED THAT THE INTEREST IN DIVERSION SUGGEST THAT THE DEVELOPMENT AND TESTING OF OFFENDER TYPOLOGIES IS CRITICAL FOR THE NEEDS OF THE IMMEDIATE FUTURE. I-LEVELS MIGHT BE AN APPROPRIATE INSTRUMENT WHEN INTENSIVE TREATMENT CAN BE USED FOR THOSE OFFENDERS THAT I-LEVELS RESEARCH INDICATES AS LIKELY TO BENEFIT FROM TREATMENT IN THE COMMUNITY. I-LEVELS RESEARCH DOES NOT SOLVE THE QUESTION OF WHETHER TREATMENT IN THE COMMUNITY MIGHT BE A USEFUL STRATEGY FOR SOME OFFENDERS. REFERENCES ARE PROVIDED. (KBL)