There exists a confusing array of statistical data regarding the use and misuse of substances. The most important distinction to make when considering data is that between the prevalence of lifetime use and active problem/dependent misuse. For example, whilst roughly 50% of 16-29 year olds have used an illicit substanceat least once in their lifetime, only 2% of the general population is actively dependent on an illicit substance. Many more, however, use substances in a way which causes harm to themselves and/or others (misuse). In fact by far the most common forms of substance misuse are legal and not illicit – nicotine and alcohol are responsible for the large majority of health, social problems and dependency created by substance misuse. Approximately 15% of the adult population experience problems as a result of alcohol misuse, whilst many more are dependent on nicotine