The influx of “crack” cocaine led to the growth of the 1980's street gang culture in America's cities. Along with drug use, abuse, and trafficking came abundant firearms and escalating violence. Juvenile homicides and armed assaults spiraled, as gang members became entrenched in a repetitive cycle of destruction. In Boston, probation officer Bill Stewart observed the failure of conventional office practice to influence individual youths whose dangerous lifestyle promised death or long incarceration. Moving into the streets, using gang language and style, his team learned that the large majority of gang members were motivated, at some level, to respond to believable authority. More demanding terms of probation, notably curfews and association rules for offenders, and nightime street presence backed by police have changed the impact of department's work. The combination of mentoring and enforcement, along with authentic use of the probation officer's personality, creates the opportunity for violent young people to communicate with the officer and to make constructive choices.