Former prime minister Helen Clark has joined a number of high-profile world leaders on the Global Commission on Drug Policy.
The commission is an independent body that advocates for science-based discussion about effective ways to reduce the harm caused by drugs to people and societies.
Last month it issued a report on effective responses towards the opioid overdose crisis in North America.
Ms Clark joins former UN secretary-general Kofi Annan, Nobel Peace Prize recipient Jose Ramos-Horta, businessman Sir Richard Branson and former presidents of Poland, Colombia, Nigeria and Greece on the commission.
Ross Bell, the Drug Foundation's executive director, says having Ms Clark involved is a coup for New Zealand.
"The commission has become well known for championing cutting edge, health-focused approaches to drug problems," he said.
"While her role will be globally focused, it's likely New Zealand will find ways to involve her in the domestic discussions we will soon be having about health approaches to drugs and cannabis law reform."