As evidenced by inmate drug tests, inmate overdoses, drug finds in the institutions, and other information sources, illegal drugs are present in almost all BOP institutions. The BOP's strategy for preventing drugs from entering its institutions uses two major components: stopping the supply of drugs through various interdiction activities and reducing the demand for drugs through drug abuse treatment for inmates. Interdiction efforts focus on the institutions' points of entry, such as visitors, staff, mail, the receiving and discharge area, the warehouse, the rear gate, volunteers, and contractors. To reduce the demand for drugs among inmates, the BOP offers drug abuse treatment to inmates through various institution-based programs. The OIG found that inmate visitors, staff, and the mail were the three primary ways drugs have been entering BOP institutions. Interdiction efforts have failed to prevent drug smuggling by staff. Interdiction measures that are common in many State correctional systems, such as searching staff, limiting the personal property staff are permitted to bring into the institution, and conducting random drug tests of staff, are not used by the BOP. The OIG also found that an insufficient number of inmates receive drug treatment, partly because the BOP underestimates and inadequately tracks inmates' treatment needs. In addition, nonresidential treatment, an important component of drug treatment, is not adequately provided at BOP institutions. Fifteen recommendations are offered for making the BOP's drug interdiction and treatment efforts more effective. 6 tables