Book excerpt: Abuse of drugs and alcohol may cause serious difficulties at work including deterioration in job performance. Abuse is caused by a range of personal, family, social or work situations or a combination of such factors. This report presents a variety of multidisciplinary approaches to the prevention, assistance, treatment and rehabilitation of alcohol- and drug-related problems in the workplace. Although experience has shown the difficulty of eliminating substance abuse, the policies presented are likely to yield constructive results for workers and employers alike.