Implementation of injectable heroin treatment for patients with chronic heroin dependence unresponsive to oral methadone maintenance treatment has stagnated, even though the evidence for its effectiveness in this population continues to accrue. This is due to a range of political and environmental factors, not least of which is the cost of the treatment. The article by Byford et al in this issue of the Journal goes some way to increasing the evidence base for the cost-effectiveness of injectable heroin treatment compared with other treatment options. Questions still remain though about the funding implications for government departments, commissioners and providers, given that the sector that is responsible for the majority of the cost, healthcare, is not the same sector that sees the majority of the cost savings, criminal justice.