This report presents the recommendations of a WHO Expert Committee responsible for reviewing information on dependence-producing drugs to assess the need for their international control. The first part of the report contains a description of the procedure for the review of dependence-producing substances. This is followed by a critical review of five psychoactive substances (amfepramone amineptine buprenorphine delta-9-tetrahydrocannabinol and tramadol). The report also discusses the substances that were pre-reviewed by the Committee four of which (ketamine zopiclone butorphanol and khat) were recommended for critical review at a future meeting. The final section discusses the problems of the terminology used in reporting abuse-related adverse drug reactions and describes how confusion affects the reporting of adverse effects using the example of the selective serotonin reuptake inhibitors.