In March 2006, the Government of Jamaica engaged the Millennium Institute to assist in the development of a modern planning tool with the capability to integrate relevant sectors of the Jamaican society. An important component of the model is the sector for organized crime behaviour in Jamaica. The purpose of this paper is to explain the development of the organized crime sector within the T-21 Jamaica model and demonstrate the possible utility of system dynamics in facilitating discussions on public policy. The organized crime sector examines the conversion of young, unemployed males living in impoverished, urban areas into gang members and some possible outcomes of this behaviour. The validity of the model is tested by its ability to match Jamaica's historical data for gang-related murders and shootings.Possible interventions are explored with the model suggesting that social interventions would have a more immediate impact on reducing crime rates but increased investment in the security forces would eventually lead to an even greater reduction in crime in the long run.