The Correctional Service of Canada implemented a urine drug-testing program over a decade ago. Offenders residing in federal correctional institutions and living in the community on conditional release were subject to urine drug testing. The objective of this study is to describe this testing program and the extent of drug use by conditional release offenders in 2000. Urine specimens were tested for drugs of abuse and prescription drugs including amphetamines, cannabinoids, cocaine metabolite, opiates, phencyclidine, benzodiazepines, methyl phenidate, meperidine, pentazocine and fluoxetine by immunoassay screening followed by GC-MS confirmation. Ethyl alcohol was analyzed when specifically requested. Alternative screening and confirmation methods with lower cut-off values were used whenever urine specimens were dilute (creatinine <20 mg/dL and specific gravity <or=1.003). Total number of urine specimens analyzed in 2000 was 38,431 (6.7% were dilute). The positive rate for one or more drugs was 27.2% in 2000 in conditional release offenders. In the community setting 28,076 normally concentrated (nondilute) specimens were tested (9.6% were positive for cannabinoids and 3.3% positive for cocaine metabolite). In the 1,270 dilute specimens collected from conditional release offenders in 2000, 12.8% were positive for cannabinoids and 10.6% were positive for cocaine metabolite. The authors conclude that forensic urine drug testing provides an objective measure of drug use when assessing offenders living in the community on conditional release from correctional institutions in Canada.