The authors sampled for expanded drug testing of 1,061 urine specimens collected by Maryland Division of Parole and Probation staff. They found an increase in the percentage of individuals testing positive for buprenorphine and found that these specimens often contained other drugs, suggesting misuse. Subsequent interviews with 15 probationers and parolees in Baltimore, Maryland, showed wide-scale availability of buprenorphine on the street and in prisons. Medical examiners and drug testing programs should immediately initiate routine testing for buprenorphine to track a possible outbreak of buprenorphine diversion and misuse. Physician education programs should redouble their efforts to teach strategies to deter diversion and misuse of the drug.