INTRODUCTION : ILLEGAL DRUG MARKETS , RESEARCH AND POLICY by Mike Hough South Bank University , London

Illicit drug use is widespread across most industrialised countries. The prevalence of illicit use is probably measured best in the United States: at least 14 million people, or 6% of the population, use illicit drugs every month (Office of National Drug Control Policy [ONDCP], 1999). Nor is this pattern of use confined to the U.S. In Britain, for example, around 2 million people use illicit drugs each month, representing 6% of the population aged 16 to 59 (Ramsay and Partridge, 1999). Only the brave would try to make a precise count of global annual production of illicit drugs. There are some "order of magnitude" figures, however. For example the annual global production of heroin has been put at 550 tonnes (metric tons) per year in the 1990s; the corresponding figure for cocaine in 1996 was 1,000 tonnes (United Nations Drug Control Programme [UNDCP], 1997). Some countries have estimated levels of consumption, though these estimates will also be subject to wide margins of error. In the U.S., the figure for expenditure on illicit drugs in 1995 was put at $57 billion (ONDCP, 1997a). The corresponding figure for the U.K. is £3.9 billion to £8.5 million (Office of National Statistics [ONS], 1999). Even allowing for very substantial imprecision, these figures suggest that the illicit