In the UK, drug misuse gives rise to between £10 billion and £18 billion a year in social and economic costs, 99% of which are accounted for by problematic drug users. There are strong links between problematic drug use and crime. The Drug Interventions Programme (DIP) is a critical part of the Government’s strategy for tackling drugs.  The implementation of the UK Drug Intervention Programme poses a number of challenges.  This includes providing a through-life approach to drug user treatment management.  This must take place within a multi-agency system some of which have been newly formed. This paper discusses a study working with one such coordinating body – Lancashire Drug Action Team (DAT) in its Drug Intervention Programme (DIP) strategy.  Initial work has focused on Aftercare Services in the Burnley area. A systems modelling approach using System Dynamics has been adopted.