What works to reduce harm from alcohol and other drugs: evidence of effectiveness
Worldwide, it is well understood that alcohol and other drug harm affect wellbeing and mental health outcomes, both for those with lived and living experience of drug harm, their families and communities. There have been internationally recognised and groundbreaking harm reduction initiatives introduced in Aotearoa New Zealand but there is potential to do much more.
The need for action was identified in He Ara Oranga, the 2018 inquiry into mental health and addiction. Chapter 9 in the report highlighted alcohol and other drugs as a key area where stronger, more coordinated responses are needed. Read He Ara Oranga chapter
Why we commissioned this work
The Mental Health and Wellbeing Commission has monitored addiction treatment services over recent years, including through a data summary on addiction services published in May 2025 and our system performance monitoring. Harm reduction, however, is a relatively new focus area for the Commission, and our approach takes a broader view of the change we want to see at a system level to reduce harm for people..
In order to effectively advocate for approaches that reduce alcohol and other drug harm, we first need to understand what has been shown to work and how those approaches fit within the unique context of Aotearoa New Zealand.
As part of our 2025–26 work programme, we commissioned a substantive Literature review along with an Evidence brief on “what works” to reduce alcohol and other drug harm..
This work sits under our strategic priority to advance mental health and wellbeing outcomes for people with lived experience of mental distress and addiction. It supports the outcome that “people have reduced harm from alcohol and other substance use”.
What the evidence shows
The findings are clear: decisions to reduce alcohol and other drug harm in Aotearoa New Zealand should be grounded in evidence and lived experience. This is critical to improving mental health and wellbeing outcomes for people and communities.
Reducing harm also means addressing the social and structural factors that drive inequities in people’s experiences and outcomes. Harm reduction approaches are most effective when they are shaped by the people and communities most affected.
The evidence shows that harm reduction approaches can be effective and cost effective. A public health approach to alcohol and other drug harm requires a stronger focus on harm reduction within health investment and service design.
Next steps
The focus is on evidence based solutions of what works to reduce harm from alcohol and other drugs at a system level. Our goal is to ensure sector leaders, providers and decision makers are making evidence informed decisions that will result in improved outcomes for people.
There are several approaches supported by the evidence that we will be advocating for going forward. A webinar to discuss some of these approaches is also being planned.