Study 1 examined the prevalence of sexual dysfunction in 101 male alcohol addicts. Inpatients at a clinic for alcoholism were investigated by questionnaire about their sexual functioning and by hormonal data. Three-quarters had erectile dysfunction, loss of libido, and premature or delayed ejaculation. A follow-up study was done 9 months after the end of treatment. No significant differences in the prevalence of sexual dysfunction were found between the two points of measurement. All patients had normal levels of plasma testosterone at the beginning and end of inpatient treatment. These findings suggest psychological causes for the sexual problems and a need for therapeutic intervention. Study 2 reports on a group of addicts with sexual dysfunction who were treated by a behavioral treatment format. Follow-up results indicate that the treatment group showed significantly less sexual dysfunction than an untreated control group.