Percentage of arrests was determined for a sample of 254 addicts who did not complete the Phoenix House Program (dropouts) and 104 who were in the last stages of the program. Results showed that the longer the residence the larger the postprogram reduction, eg, dropouts after 12 months' residence showed a 70% change in arrests in one year of followup. It was concluded that addicts with any residential experience in Phoenix, even those who failed to complete the program, showed sharp reductions in criminal activity during and after leaving the program. These changes relate to rehabilitative aspects of the program.