THE DRUG ABUSE AND DELINQUENCY ANALYSIS IS PART OF A LARGER SURVEY CONCERNED PRIMARILY WITH THE CAUSES AND EFFECTS OF DROPPING OUT OF HIGH SCHOOL. IN 1966, THE INITIAL SAMPLE OF 2,200 10TH-GRADE BOYS ANSWERED QUESTIONS ABOUT THEIR BACKGROUNDS, ATTITUDES, BEHAVIOR, PLANS, VALUES, AND COGNITIVE ABILITIES. FOUR FOLLOWUP STUDIES WERE CONDUCTED IN 1968, 1970, AND 1974. FULL FOLLOWUP INFORMATION WAS OBTAINED FOR 73 PERCENT OF THE ORIGINAL SAMPLE. STATIC ANALYSES OF THE RELATIONSHIP BETWEEN NONADDICTIVE USE OF ILLICIT DRUGS AND OTHER FORMS OF DELINQUENT BEHAVIORS REVEAL THE FOLLOWING: (1) ILLICIT DRUG USE IS RELATED POSITIVELY AND STRONGLY TO OTHER FORMS OF ILLEGAL BEHAVIOR; (2) GREATER INVOLVEMENT WITH DRUGS IS ASSOCIATED WITH HIGHER EXPECTED LEVELS OF DELINQUENCY; (3) CRIMES AGAINST PROPERTY ARE MORE RELATED TO ILLICIT DRUG USE THAN ARE CRIMES AGAINST PERSONS; (4) MINOR THEFT, SHOPLIFTING, AND TRESPASSING BEAR A PARTICULARLY STRONG RELATIONSHIP TO ILLICIT DRUG USE; (5) HEROIN USE IS LESS RELATED TO THE COMMISSION OF MINOR THEFT THAN IS THE USE OF OTHER ILLICIT DRUGS BUT MORE RELATED TO MAJOR THEFT AND TO THE THEFT OF CAR PARTS; AND (6) YOUNG MEN WHO USE ONLY MARIHUANA HAVE LOWER INDEXES OF DELINQUENCY THAN DO OTHER DRUG-USING GROUPS AND HAVE LEVELS OF INTERPERSONAL AGGRESSION COMPARABLE TO THOSE OBSERVED FOR ABSTAINERS. CROSS-TIME ANALYSES SHOW THAT MOST DIFFERENCES IN DELINQUENCY BETWEEN USERS AND NONUSERS OF DRUGS EXISTED BEFORE DRUG USAGE EVER BEGAN. THERE IS NO EVIDENCE OF A LASTING IMPACT OF DRUG USE ON DELINQUENCY LEVELS; I.E., NO CAUSAL LINK BETWEEN DRUG USE AND DELINQUENCY IS INDICATED. IT IS CONCLUDED THAT THE NONADDICTIVE USE OF ILLICIT DRUGS DOES NOT PLAY A SIGNIFICANT ROLE IN LEADING PEOPLE TO COMMIT CRIMES. IT SEEMS MORE PLAUSIBLE THAT DELINQUENCY LEADS TO DRUG USE. IT IS POSSIBLE THAT DELINQUENTS WHO BECOME PART OF A DEVIANT PEER GROUP ARE MORE LIKELY TO BECOME DRUG USERS BECAUSE DRUG USE IS AN APPROVED BEHAVIOR IN SUCH A PEER GROUP. SUPPORTING DATA AND A LIST OF REFERENCES ARE INCLUDED. (LKM)