Attitudes, perceived social norms, and intentions were assessed for 376 counselors and 1,083 clients from outpatient, methadone, and residential drug treatment programs regarding four medications used to treat opiate dependence: methadone, buprenorphine, clonidine, and ibogaine. Attitudes, social norms, and intentions to use varied by treatment modality. Methadone clients and counselors had more positive attitudes toward the use of methadone, whereas their counterparts in residential and outpatient settings had neutral or negative assessments. Across modalities, attitudes, perceived social norms, and intentions toward the use of buprenorphine were relatively neutral. Assessments of clonidine and ibogaine were negative for clients and counselors in all settings. Social normative influences were dominant across settings and medications in determining counselor and client intentions to use medications, suggesting that perceptions about beliefs of peers may play a critical role in use of medications to treat opiate dependence.