"The Single Convention on Narcotic Drugs of 1961 was set up as a universal system (replacing the various treaties signed until then) to control the cultivation, production, manufacture, export, import, distribution of, trade in, use and possession of narcotic substances, paying special attention to those that are plant-based: opium/heroin, coca/cocaine and cannabis. More than a hundred substances are listed in the four schedules of the convention, placing them under varying degrees of control.
"The Convention on Psychotropic Substances of 1971, in response to the diversification of drugs of abuse, introduces controls over the licit use of more than a hundred-largely synthetic- psychotropic drugs, like amphetamines, LSD, ecstasy, valium, etcetera, again divided over four schedules. An important purpose of the first two treaties is to codify internationally applicable control measures in order to ensure the availability of narcotic drugs and psychotropic substances for medical and scientific purposes, while preventing their diversion into illicit channels. The World Health Organization (WHO) is responsible for the medical and scientific assessment of all psychoactive substances and to advise the Commission on Narcotic Drugs (CND) about their classification into one of the schedules of the 1961 or 1971 treaties.
"In response to the increasing problem of drug abuse and trafficking during the 1970s and 1980s, the Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances of 1988 provides for comprehensive measures against drug trafficking. These include provisions against money laundering and the diversion of precursor chemicals, and agreements on mutual legal assistance. The International Narcotics Control Board (INCB) is the quasi-judicial control organ for the implementation of all three United Nations drug conventions. The board consists of thirteen members, three elected from a list of candidates nominated by WHO and ten from a list nominated by Governments."

Source

Organization of American States, Inter-American Drug Abuse Control Commission, and Caribbean Community Secretariat, "How to Develop a National Drug Policy: A Guide for Policymakers, Practitioners, and Stakeholders," (Washington, DC: 2009), p. 51.
http://www.cicad.oas.org/en/p…