There are about 28,500 people who inject drugs (PWID) in Nepal and HIV prevalence among this group is high. Nepal introduced harm reduction services for PWID much earlier than other countries in South Asia. Methadone maintenance treatment (MMT) was first introduced in Nepal in 1994. This initial small scale MMT programme was closed in 2002 but reopened in 2007 as an emergency HIV prevention response. It has since been scaled up to include three MMT clinics and continuation of MMT is supported by the Ministry of Home Affairs (MOHA; the nodal ministry for drug supply reduction activities) and has been endorsed in the recent National Narcotics policy. Pressure from drug user groups has also helped its reintroduction. Interestingly, these developments have taken place during a period of political instability in Nepal, with the help of strong advocacy from multiple stakeholders. The MMT programme has also had to face resistance from those who were running drug treatment centres. Despite overcoming such troubles, the MMT programme faces a number of challenges. Coverage of MMT is low and high-risk injecting and sexual behaviour among PWID continues. The finance for MMT is largely from external donors and these donations have become scarce with the current global economic problems. With a multitude of developmental challenges for Nepal, the position of MMT in the national priority list is uncertain. Ownership of the programme by government, a cost-effective national MMT scale up plan and rigorous monitoring of its implementation is needed.