A background discussion reviews the pros and cons of employee drug testing, current testing methodology and terminology, and features of the most commonly abused drugs (marijuana, stimulants, sedatives, opiates, and hallucinogens). An examination of the legal issues focuses on statutory restrictions, employee privacy, potential discrimination claims, defamation risks, wrongful discharge, and restrictions in the union setting. Suggested employee guidelines for drug testing are to seek employee and union input, limit testing to reasonable circumstances, select the testing methodology and laboratory carefully, and provide additional safeguards such as procedures for employees' to challenge testing results and confidentiality of test results. 33 notes.