This paper presents findings from a study which identified 2,525 dual participants utilizing public sector alcohol treatment programs. The dual participant study population was highly representative of the 30,801 MODDP-only participants with regard to demographic characteristics. Over one-half of the dual participants had their initial admission into residential treatment programs which serve individuals who generally have serious and chronic alcohol-related problems. Study findings strongly support the need for drinking driver programs to be aware of the high risk group of dual participants and for alcohol-related treatment programs to provide drinking and driving education to all dual participants who drive. (Author abstract modified)