The description outlines the conceptual roots and evolution of the Intervention Approach and the Weekend Intervention Program and includes a review of the data to evaluate the program's impact and process. Major programmatic goals of the intensive, 3-day WIP residential program to which persons involved in a drug or alcohol offense may be remanded by a court or other supervising agency include: to provide a comprehensive assessment of an individual's involvement with alcohol and other psychoactive drugs; to confront participant denial and encourage self-evaluation; and to prepare participants for treatment when necessary and increase their accessibility to treatment. A study of recidivism rates was conducted among offenders who were sentenced to jail for several days compared with those receiving a suspended sentence/fine and those remanded to the WIP. Repeat offenders consistently did worse than first-time offenders, but, with repeaters, the WIP enjoyed a lower recidivism rate than the other two groups. This investigation suggests that recidivism could be reduced if the referring court mandated the post-WIP treatment recommendations made by the WIP staff. 2 figures and 14 references (Author abstract modified)