SERIOUS THIEVES WERE THOSE WHO LABLED THEMSELVES AND WERE LABELED BY PEERS AS THIEVES AND WHO GAINED SPECIFIED INCOME FROM THEIR THIEVING. DATA WERE COLLECTED BY OBSERVATION AND BY STRUCTURED, INDEPTH INTERVIEWS WITH 40 SERIOUS THIEVES, 2 NONTHIEVING PEERS, 2 PROFESSIONAL THIEVES, AND 4 FENCES. EACH INTERVIEW LASTED BETWEEN 90 AND 120 MINUTES. RESULTS SHOWED THAT THE YOUTHS USUALLY CAME FROM SOCIALLY AND ECONOMICALLY HANDICAPPED FAMILIES, WERE SCHOOL DROPOUTS, AND HAD IRREGULAR WORK HISTORIES. THEIR TIME WAS LARGELY SPENT WITH OTHER THIEVES, FENCES, AND CRIMINALS WHO PROVIDED THE RECRUITMENT, TRAINING, AND MORAL SUPPORT REQUIRED FOR REGULAR THIEVING. THUS, THEIR THIEVING WAS RATIONALLY ORGANIZED SO THAT IT TOOK ON THE QUALITIES OF AN OCCUPATION. THEIR SIX SPECIALIZED WAYS OF STEALING INCLUDED SHOPLIFTING, HOME BURGLARY, COMMERCIAL BURGLARY, CLOUTING (STEALING GOODS IN TRANSIT), VEHICLE THEFT, AND, LESS FREQUENTLY, FRAUD AND FORGERY. SERIOUS THIEVING IS THEREFORE A LOW-SKILLED, SHORT-TERM OCCUPATION WITH LIMITED FINANCIAL GAINS. SECRECY AND TRUST ARE ESSENTIAL FOR SERIOUS THIEVES' OPERATION. CAREERS ARE PUNCTUATED BY ARRESTS, CONVICTION, AND IMPRISONMENT. SITUATIONAL CHANGES SUCH AS AN ACCUMULATION OF ARRESTS OR MARRIAGE OFTEN CAUSED THESE THIEVES TO ABANDON THEIR ROLES AS THIEVES. THE EXODUS FROM THIEVERY REFUTES SOME OF THE CRUDER STATEMENTS OF LABELING THEORY AND SUGGESTS THAT CRIME IN TORONTO MAY DIFFER FROM CRIME ELSEWHERE. IT IS CONCLUDED THAT SERIOUS THEFT EXISTS AS AN ONGOING ACTIVITY THROUGH ITS INTEGRATION WITH THE COMMUNITY. IT IS ENACTED WITHIN A NEGOTIATED SOCIAL ORDER RELYING LARGELY ON TRUST. TABLES AND A REFERENCE LIST ARE INCLUDED. (CFW)