The Prime Minister avoided a verbal lashing in his meeting with the unpredictable leader of the Philippines.
John Key met Rodrigo Duterte for the first time at the East Asia Summit in Laos, where drugs and human rights dominated a brief conversation.
US President Barack Obama cancelled a similar meeting, after Duterte called him a "son of a whore", for opposing the Philippines' bloody drugs war.
Key was "quite direct" with the Duterte in expressing New Zealand's opposition to his methods in this war on drugs.
"He wasn't overly defensive, but he made the point once again that he's got a belief in how these drugs are coming into the Philippines and he believes his track record of being absolutely resolute is something that has worked," Key told reporters after the meeting.
Key says the Filipino president's hard line against drug pushers is intended to save the lives of three million drug addicts in the country, but he believes traffickers could be held to account in a way that would ensure innocent people wre not caught up in the system.
Key earlier met Russian Prime Minister Dmitry Medvedev, who had warned of "a tough conversation" with regards to Russia voting to discourage Helen Clark in her bid become the next United Nations Secretary-General in favour of an Eastern European candidate.
They also discussed Russia's military intervention in Syria.
"We're interested in your take on the situation in Syria given we are in the presidency of the Security Council this month," Key told Medvedev.
In a meeting with Laos Prime Minister Thongloun Sisoulith, Key pledged $11.5 million and a trial of New Zealand technology to help clear millions of Vietnam War-era unexploded ordnances in Laos.
"Many decades on, this country still has a huge number of unexploded bombs - they think on the current rate it will take 80 years to clear Laos - and of course the great tragedy is these little bombs are the sorts of things that a child might pick up," he said during a visit to an unexploded ordnance training facility.
The main event was the Summit itself, during which the leaders spoke and addressed issues of concern, including disputes over the South China Sea.
Some leaders took the opportunity to celebrate their nations' success over the Kiwis at the Olympics.
"[I was] taking a hard time from the Japanese Prime Minister about how the Mighty Blossoms beat the All Blacks and from the Australian Prime Minister that our girls lost in the final," Key said.
Key is now in the air, on his way from the summit in Laos to a forum in Micronesia.
He said fisheries and economic issues will also crop up, but climate change will dominate the talks.