The 56 identified hot spots of drug activity were randomly divided into two groups, and the existing six narcotics squads (each comprising one sergeant and five detectives) of the Jersey City Police Department were randomly assigned to experimental and control hot spots. In the 28 experimental hot spots, the law enforcement strategy consisted of three stages: planning, implementation, and maintenance. In the planning stage, officers collected information about drug activity, met with business owners and residents, and developed case files on suspected drug offenders. During implementation, officers used intensive crackdowns and coordinated efforts that involved local government agencies (housing and beverage licensing) to close down drug activity. In the third stage, officers maintained gains made during implementation by close surveillance, foot patrols, and other forms of police presence as they were alerted to new drug activity. The study shows that an innovative drug enforcement strategy can be effective in reducing a key indicator of crime and disorder, i.e., emergency calls for service. The researchers further concluded that focused enforcement efforts do not necessarily lead to displacement of crime problems to surrounding areas.