Donald Trump is not on the G-20 Hangzhou guest list and neither he nor the U.S. Presidential race are on the official agenda. But he's there in spirit.
No doubt it will be a tortuous road to the U.S.'s November elections and a seat in the Oval Office. But the risk of a Trump Presidency and more importantly, what it means for global trade, will almost certainly be privately debated and agonized over by leaders and diplomats here in Hangzhou in eastern China.
"Public sphere, we can expect more bland statements about all working to get the recovery on track," one head of research at a European bank tells me. "Backstage, I imagine real tension and panic," emanating from November's U.S. election and European elections in 2017.
Needless to say such stress testing of Grey Swans, Black Swans and what some cheekily describe as the "Orange Swan" event will be safely confined to the sidelines of this power gathering. Nevertheless, we'll be keeping our ears to the ground.