THE KNOWLEDGE THAT SOCIAL SCIENTISTS HAVE ABOUT DRUG ABUSERS AND DRUG ABUSE HAS BEEN OBTAINED FROM A POPULATION DEFINED AND OFTEN PROVIDED BY THE CRIMINAL JUSTICE SYSTEM. AS A RESULT, THIS KNOWLEDGE HAS BEEN LIMITED, GENERALLY, TO THOSE WHO USE ILLICT DRUGS. IN THIS PAPER, SELECTED SOCIAL AND DEMOGRAPHIC CHARACTERISTICS AND DRUG USE PATTERNS OF A POPULATION OF COUNTY HOSPITAL EMERGENCY ROOM DRUG OVERDOSE CASES WERE EXAMINED AND COMPARED TO A POPULATION OF DRUG USERS IN DRUG TREATMENT PROGRAMS IN THE SAME COUNTY. IF WAS FOUND THAT DRUG USERS WHO CAME TO THE EMERGENCY ROOM, IN COMPARISON WITH DRUG USERS IN TREATMENT, WERE MORE LIKELY TO BE FEMALE, OLDER AND ABUSERS OF PRESCRIPTION DRUGS. IN ADDITION, IT WAS FOUND THAT THE EXISTING TREATMENT PROGRAMS IN THE COUNTY IN THEIR PRESENT STRUCTURE SEEM TO BE UNABLE TO PROVIDE ADEQUATE TREATMENT SERVICES TO THE DRUG-USING EMERGENCY ROOM POPULATION. (AUTHOR ABSTRACT)...DMC