There were no awkward handshakes or sexist comments that we know of - but the Prime Minister did exchange a couple of light-hearted quips with US President Donald Trump while at Apec in Vietnam.
Interviewed by Newsroom on the flight home, she revealed that while waiting for an introduction at the East Asia Summit gala dinner, Trump "in jest patted the person next to him on the shoulder, pointed at me and said, 'This lady caused a lot of upset in her country', talking about the election".
"I said, 'Well, you know, only maybe 40 per cent', then he said it again," she told Newsroom.
"I said, 'You know', laughing, 'no-one marched when I was elected'."
The president just laughed, she said.
"It was only afterwards that I reflect that it could have been taken in a very particular way - he did not seem offended."
After winning the election Ardern spoke with Trump on the phone for around five minutes. She said he had "genuinely been interested" in the election, which had been extensively covered in the US media.
The prime minister also managed to make a potential insult to Trump seem like a compliment this week.
In a Q&A with the Herald's Audrey Young she said her abiding impression of Donald Trump, after speaking with him a few times, was that he was "consistent".
"He is the same person that you see behind the scenes as he is in the public or through the media," she said. Asked if that was a compliment she said "I think being consistent - there is something in that."