The aims of developing the lexicon are to support the UN Declaration on Demand Reduction by defining key terms employed in the Declaration itself, in the wider medical and scientific literature concerned with 'demand reduction', to define terms used in connection with 'supply control' activities and to define key terms employed in international treaties concerned with illicit drugs. Another aim is to facilitate international communication about drug issues and policies by providing a reference point for drug-related terms, acknowledging different sets of preferred terminologies and providing alternative definitions of key terms and referencing these to major sources.