After 3 years of researching and analyzing data on 142 offender drug testing programs across the United States, the NCJA concluded that cost is the primary consideration affecting State and local criminal justice official decisions about drug testing programs. The NCJA identified three classes of costs and impacts associated with implementing drug testing programs for criminal justice populations: (1) testing preparation costs; (2) testing management and administrative costs; and (3) testing outcome costs incurred by criminal justice and related social service agencies to sanction and/or provide treatment services for drug-involved offenders identified through drug testing. The NCJA found that several drug testing programs had adopted uniform procedures to guide the physical administration of drug tests and the selection of vendors to supply testing materials and services. Individual drug testing program officers, however, often made the decisions about testing frequency and actions to be taken in response to positive tests. Consequently, testing policies and responses to positive test findings varied significantly, even within a program testing the same target population under the general authority of a single agency. Considerable variation was also observed among State and local official choices of drug testing technologies and in the selection of vendors to provide drug testing materials, equipment, and laboratory and other services. The selection of testing technologies appeared to be influenced most often by factors related to the way in which tests were to be conducted and the way in which results were to be used. Of the 142 offender drug testing programs, 15 local and two State programs tested arrestees for drug use, 18 local and 32 State programs tested incarcerated offenders, 38 local and six State programs tested probationers, nine State programs tested parolees, and four local and 18 State programs tested both probationers and parolees. Arrestee drug testing programs generally targeted arrestees under consideration for pretrial release. Testing programs for incarcerated offenders generally tested inmates in confinement or on work release. The cost of a single drug test ranged from 93 cents to $5.30, while fixed costs for multiple drug tests ranged from $2.50 to $27.27. These costs varied somewhat, depending on the target population being tested. Cost factors influenced the selection of testing technologies, the number of offenders to be tested, testing frequency, confirmation of positive tests, and the development of and adherence to policies prescribing administrative and disciplinary actions for positive tests. Supporting tabular data and worksheets