Substance misuse and abuse exist in almost every human society. In our western civilization, the bulk of attention has focused on those indi viduals who specifically seek treatment or those who have become so disabled by these problems that they require treatment. These indi viduals usually qualify for a psychiatric diagnosis of alcohol or other substance abuse. However, just as it has been recognized that primary substance abuse is frequently associated with other diagnosable psychi atric disorders, such as sociopathy or attention deficit disorder (residual type) and that the origins of substance abuse are multivariate, we have also begun to become aware that many other individuals in our society with psychiatric or other problems also suffer, to varying degrees, from substance abuse. These problems may be considered secondary by vari ous specialists or treatment personnel; but nevertheless, they are prob lems, and what disorder is primary or secondary in a given individual may often be very difficult to determine in a meaningful fashion. Thus, within the past decade, research studies have reported significant inci dences of substance abuse/or misuse in high school and college-aged populations, in medical populations, and in individuals with other psy chiatric disorders such as schizophrenia, depression, and the anxiety and personality disorders. Yet to date little has been done to bring together and systematize this widely scattered data that describes the presence of substance abuse problems in various populations.