On the trade front he had to deal with the Trans Pacific Partnership negotiation, the Russian free trade agreement on the go and a prospective free trade agreement with Colombia to get under way after the visit by Prime Minister John Key there in March.
His next trip will be to Colombia within a couple of weeks.
He will be discussing the Russia trade negotiations on the side-lines of an OECD meeting in Paris at the end of May.
But he is especially upbeat about Japan joining the Trans Pacific Partnership negotiations and had talks with key ministers in Japan last week.
"I think we have a unique opportunity to revitalise our relationship with Japan through TPP. That's potentially huge. "
New Zealand's exports to Japan were worth $4 billion 20 years ago and they had declined about 25 per cent.
"That's not good for us and I think TPP offers a wonderful opportunity to revitalise our economic relationship with Japan."
President Barack Obama has set October this year as a deadline to reach agreement on the TPP and Mr Groser, when asked about potential delays with Japan now joining, said: "We are quite determined to avoid the eternal delays that bogged the whole process of the WTO down - it doesn't make it easier to make decisions but we will keep the pressure on."
Mr Groser said he would make no comment on the remaining contest for the WTO which has to be decided by May 31.
The 12 countries negotiating the TPP are New Zealand, Singapore, Brunei, Chile, United States, Australia, Peru, Vietnam, Malaysia, Canada, Mexico and Japan.