Global Drug Survey (GDS) is an international research organisation focused on drug and alcohol use, related health outcomes, and harm reduction. It conducts anonymous online surveys designed and analysed by experts in epidemiology, addiction, criminology, toxicology, and sociology. Its research draws on data from more than 500,000 people across over 50 countries, helping researchers, services, and policymakers examine patterns of use, regional differences, personal decision-making, and emerging trends.

GDS offers participant recruitment and survey design, data analysis and reporting, digital health apps, consultancy and training, and expert witness and legal opinion services. Its reports and findings cover topics including drug policy, cannabis, psychedelics, alcohol, and drink spiking. The organisation also provides free online tools and harm-reduction resources, including Drinks Meter, Drugs Meter, Drugs Meter Mini, Safer Use Limits, One Too Many, and The Highway Code. These services aim to support better understanding and safer choices around drug and alcohol use, irrespective of the legal status of a substance. GDS also shares research through academic articles, media partnerships, and online resources.