The Forty-seventh Meeting of the World Health Organization (WHO)’s Expert Committee on Drug Dependence (ECDD) was convened from 14 to 18 October 2024 and was coordinated from the WHO headquarters in Geneva. The Forty-seventh WHO ECDD critically reviewed eight new psychoactive substances, comprising one synthetic cannabinoid (hexahydrocannabinol), four novel synthetic opioids (protonitazepyne, metonitazepyne, etonitazepipne, N-desethyl isotonitazene), one dissociative-type substance (3-hydroxyphencyclidine) and one cathinone/stimulant (carisoprodol). A critical review to consider international scheduling measures was undertaken for each substance so that the Expert Committee could consider whether information about these substances may justify the scheduling or a change in scheduling of a substance in the 1961 or 1971 Conventions. This report summarizes the findings of the forty-seventh ECDD meeting.