Detailed guidelines are presented for urine specimen collection. Although urine specimen collection requirements are stated in the guidelines, a more detailed collection procedure is presented in the Urine Specimen Collection Handbook. The guidelines specify the required features of the collections site, the donor's responsibilities, and procedures for collecting urine specimens. Guidelines for drug testing require the use of an immunoassay test cleared by the Federal Drug Administration. If the immunoassay test is positive, indicating that the specimen contained one or more drugs tested, then confirmatory testing with gas chromatography/mass spectrometry is required in order to definitively establish the identity of the drug or drug metabolite. The required cutoffs of the guidelines for the initial and confirmatory tests are presented in a table. Guidelines for specimen validity testing are also reviewed; and current dilution, adulteration, and substitution products used in attempting to "beat" a drug test are described. The U.S. Department of Health and Human Services, which is responsible for developing and monitoring Mandatory Guidelines for Federal Employee Drug Testing Programs, continues to identify and implement the most accurate and reliable drug-testing technology available. Proposals for future consideration involve alternative specimen validity testing, certification requirements, collector requirements, requirements for Medical Review Officers, initial screening process, instrumental initial test facilities, and action following the closure of public comments on proposed guidelines. 3 tables and 13 references