 The date June 26 is to commemorate Lin Zexu's dismantling of the opium trade in Humen, Guangdong, ending in June 25 1839，just before the First Opium War in China.The observance was instituted by General Assembly Resolution 42/112 of 7 December 1987.On 26 June 1987, two important texts ("Comprehensive Multidisciplinary Outline of Future Activities in Drug Abuse Control & Declaration of the International Conference on Drug Abuse and Illicit Trafficking") were adopted at the International Conference on Drug Abuse and Illicit Trafficking, which was held in Vienna during 17-26 June 1987.