Thirty active burglars in an urban area of 250,000 persons in Texas were recruited as research subjects according to a "snowball" sampling procedure. To be eligible for the study, offenders must have admitted committing a minimum of two burglaries per month and satisfied two or more of the following requirements: have been convicted by the courts or labeled by the police as a burglar, perceived themselves as burglars, and perceived by peers as burglars. The final sample consisted of 27 males and 3 females and contained approximately equal numbers of white Hispanic and black burglars. All were drug dependent or drug abusers. The study used an ethnographic format termed Staged Activity Analysis. This technique consisted of extensive interviews and "ride alongs," during which subjects were asked to reconstruct and simulate burglaries they had committed and were requested to assess dwellings that had been burglarized by other subjects. Each subject participated in as many as nine sessions. The study found that drug use and criminal activity (burglary) were inextricably interrelated. Heroin addicts were found to be more rational than previously believed and capable of controlling their drug use to a significant extent. Drug use was found to facilitate the commission of crimes for some burglars. The findings' public policy implications are discussed. 1 table, 1 figure, 3 notes, and 23 references