This briefing compiles geographically diverse evidence to enable advocates to make the case for the cost-effectiveness of harm reduction.

HIV continues to rise among people who inject drugs, yet harm reduction funding is in crisis. Financial support for an effective HIV response for people who inject drugs in low- and middle-income countries totalled US$131 million in 2019 – just 5% of the US$2.7 billion that is needed annually by 2025.

Compelling evidence from across the world shows that harm reduction interventions are cost-effective and can be cost-saving in the long-term. Advocates now need to make the investment case for harm reduction to donors and governments.

1. Needle and syringe programmes are one of the most cost-effective public health interventions in existence : An economic analysis of Australia’s 2000-2009 NSP found that, for every Australian dollar invested, more than four dollars were made in healthcare cost savings.

2. Opioid agonist therapy is cost-effective for individuals and society: A study in Indonesia estimated that expanding OAT coverage from 5% to 40% in West Java would avert approximately 2,400 HIV infections, at a cost of around US$7,000 per infection averted

3. Combined harm reduction services are significantly more cost-effective than isolated services: In Slovakia, a study found that every Euro invested in harm reduction generated benefits worth three Euros

4. The peer distribution of naloxone is highly cost-effective: One study from the United States found naloxone peer distribution to be highly cost-effective in preventing overdose-related deaths.

5. Drug consumption rooms provide a high return on investment: Researchers in the United States found that an annual investment of US$1.8 million for one supervised injection room would result in US$7.8 million in savings.

6. Inaction, reducing funds or closing services have negative economic consequences: If Switzerland had discontinued harm reduction services in 2005, modelling suggests that 1,350 more people would have acquired HIV and needed costly treatment

7. The economic cost of punitive drug policies: A study in Vietnam found detaining a person who injects drugs in a rehabilitation facility costs the local government 2.5 times more than providing them with OAT in the community for a year.