INTRODUCTION

Since 1997, the United Nations Office on Drugs and Crime (UNODC) has published estimates of the extent of drug misuse in the world. The most recent figures were presented in the World Drug Report 2005 (UNODC, 2005). It was estimated that about 200 million people, comprising 5 percent of the world's population aged 15 to 64, had used drugs at least once in the last 12 months. Cannabis was found to have been consumed by approximately 160 million people or (4% of the population aged 15 to 64). At the global level the main hard drugs reported were opiates and cocaine.

In addition to providing global estimates of drug misuse, the World Drug Report 2005 also published estimates for individual countries. The results show wide variation in the prevalence of drug use across countries. Opiate use in the last 12 months, for example, was found to range from a low of 0.01 percent in Brunei, Saudi Arabia, and Kuwait to a high of 2.8 percent in Iran. Estimates of cocaine use in the last 12 months ranged from 0.001 percent in Hong Kong to 3 percent in the United States. Cannabis use was estimated to be particularly high in some African and Caribbean countries with an estimate of 21.5 percent in Ghana and 16.1 percent in Haiti. By contrast, cannabis use was estimated to be just 0.02 percent in Brunei.