The findings of this survey constitute an important adjunct to the main measures of drug use obtained from the British Crime Survey and the national Schools Survey. The four vulnerable groups targeted by the survey were school truants and those suspended from school, young offenders, homeless youth and runaways, and youth living in drug-using families. The survey found that half of truants and those suspended from school had used an illicit drug at some time, compared with only 13 percent of school attenders. Drug use was generally higher for female than for male truants and suspendees. Three-quarters of serious and or persistent offenders had used an illicit drug in their lifetime, three times the level for non-offenders. Serious and persistent male offenders were four times more likely to be using Class A drugs monthly than similar females. Four in five homeless youth and runaways had tried an illicit drug, compared with about half of those who had never been homeless. Over 80 percent of "serial" runaways had used illicit drugs at some time compared with 42 percent of youth who had never run away from home. Drug use by parents was rare; only 3 percent had used an illicit drug in the last year, and 21 percent had done so at some time (mostly cannabis on both counts). Compared to the other vulnerable groups, associations in drug use across generations was weak. Recent drug use by older siblings was associated with higher rates among their younger brothers and sisters. 1 table and 3 references