Abstract: Since the mid-1990s, GHB – widely used in human and veterinary medicine for 30 years – has been surfacing as a recreational drug. Some EU countries have reported worries over GHB’s surreptitious use in sexual assaults. Although the extent of this is unknown, the EMCDDA and its risk-assessment partners are recommending that Member States consider the role of GHB and other drugs in this area. The risk-assessment exercise was carried out in 2000 in the framework of the Joint action on new synthetic drugs. In March 2001, the EU Justice and Home Affairs Council adopted formal conclusions that Member States should monitor this drug closely. This publication records the findings and conclusions of the exercise. Among others, it draws together the various elements used to assess the substance including: the final risk-assessment report; contributions from Europol and the European Agency for the Evaluation of Medicinal Products; a review of pharmacotoxicological data; epidemiological evidence on the associated public-health risks and sociological and criminological evidence.