World leaders and environment ministers are arriving in Germany as the UN climate talks move into their more serious and political stage.
The intense negotiations between diplomats that occupied the first week-and-a-half of talks have overall made steady progress but there are still some sticky issues for the politicians to nut out.
It's expected COP23 president Fiji will end the talks with the significant victory of getting agreement on the design of the Talanoa dialogue - discussions throughout 2018 for the world to assess how it's tracking on climate action and what more has to be done quickly.
There will also be progress made on the rule book for the Paris agreement, meaning the conference will probably end with a document agreeing to subheadings and some suggestions of what should go under them.
The deadline for the rulebook's completion is next year's conference so this is all that was really expected from 2017.
One sticky issue has been a push from developing countries for a formal discussion about pre-2020 climate action and the urgent need to raise ambitions.
"This building block is really about trust from developing countries to developed countries," Greenpeace East Asia's Li Shuo told reporters on Bonn on Tuesday, highlighting limited progress on the adaptation fund and financing, both of which would help poorer countries cope with climate change.
However, there has been a breakthrough in negotiations around agriculture issues, which Teresa Anderson from NGO ActionAid said had been bogged down for years.
The decisions to come out of COP23 should open up concrete opportunities to look at how to help vulnerable countries bring down emissions in agriculture through sharing methods and solutions that had been found to work, she said.
Australia's Carbon Market Institute is pleased with the direction of talks around a global emissions trading system.
Chief executive Peter Castellas said there had been good progress in deciding how the rules should be framed and the sector was also pleased Australian officials had taken on board its suggestions and reflected those during negotiations.
The Chinese government on Tuesday announced that once its national emissions trading scheme - expected to launch by the end of this year - has matured, it will open it up to link with global markets.
Mr Castellas said that was significant news for Australia and for the COP23 negotiations.
"If China is going ultimately to have a globally linked carbon market, we should be recognising in advance that's a market we want to be connected to and that does relate now to the types of mechanisms and market-based approaches that can be negotiated," he told AAP.
The high-level segment of the conference starts on Wednesday afternoon with a formal opening ceremony and statements from national leaders present in Bonn.
Environment Minister Josh Frydenberg is expected to make his statement on Thursday.