The Cambridge Study in Delinquent Development is a prospective longitudinal survey of 411 London males followed up from age eight onwards. This paper investigates the official crime rates of these males between the fourteenth birthday and an interview at a median age of 18 years 7 months, according to whether they were at school, in full-time employment, or unemployed. Crime rates were higher during periods of unemployment than during periods of employment . This was particularly true for offences involving material gain, at the younger ages (15–16), for the most delinquent-prone youths, and for youths with lower status jobs. However, there was little difference between crime rates just before leaving school and just afterwards in full-time employment.