The control of narcotics in Thailand has been undertaken for centuries since opium was the only known narcotic drug. The first regulation concerning opium was proclaimed in 1360 according to the Penal Code, which allowed authorized officers to imprison traffickers as well as opium addicts until they were able to overcome addiction.The Morphine and Cocaine Act of B.E. 2456 (1913) prohibited importation into the Kingdom and international trade of morphine and cocaine. Thailand also joined the International Opium Convention held in the Hague,Netherlands, in 1914. The objective of the Convention was to suppress the use of the harmful narcotics. As a result, the Narcotics Act of B.E. 2465 (1922) was promulgated to assure proper control of importation, sale, possession, production and consumption of narcotics.In 1934, the Cannabis Act was enacted to protect the public from being addicted to cannabis. And in 1939, the Kratom Act was promulgated to limit the use and propagation of Kratom trees (Mitragyna speciosa).In June 1959, the Royal Thai Government decided to abolish smoking and selling of opium after the practice had been legally allowed since the reign of King Rama IV (in around 1857). Then, came the emerging time for a new opium substitute, “heroin”, which rapidly spread among certain groups of population. The Narcotics Act of B.E.2465 (1922) was then amended and raised the maximum penalty to death sentence. In addition, the Ministry of Public Health worked in close cooperation with the Ministry of Interior on the establishment of a sanatorium for treatment of the increasing numbers of drug addicts inBangkok.The problem of narcotics does not decline and has been considered as a global problem. Modern communication and transportation facilitates smuggling and illegal distribution of harmful narcotics all over the world. SinceThailandbecame a member of the Single Convention on Narcotic Drugs of 1961, the government has put every effort in cooperation with international organizations in combating illicit trafficking of narcotics. The Narcotics Act of B.E. 2522 (1979) was consequently promulgated in order to govern the enforcement, licensing, registration, importation, exportation, manufacture, purchase and exemption of narcotic drugs.During the last decade, abuse of psychotropic substances has become a serious problem. The Thai government decided to join the International Convention on Psychotropic Substances Act of 1971. As a result, the Psychotropic Substances Act of B.E. 2518 (1975) was promulgated to control the problem.In order to face the problem of abuse of volatile substances such as thinners and lacquers which widely spread among young people, the Ministry of Public Health, therefore, promulgated the Emergency Decree on Prevention against Abuse of Volatile Substances of B.E. 2533 (1990).