"International drug convention" could mean any of several international conventions: the 1912 First International Opium Convention the 1925 Second International Opium Convention the 1925 Agreement concerning the Manufacture of, Internal Trade in and Use of Prepared Opium the 1931 Convention for Limiting the Manufacture and Regulating the Distribution of Narcotic Drugs the 1931 Agreement for the Control of Opium Smoking in the Far East the 1961 Single Convention on Narcotic Drugs the 1971 Convention on Psychotropic Substances the 1988 United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances