World leaders have held the opening session of their annual G20 summit, with any number of disputes and disagreements on the table.
Host president, Argentina’s Mauricio Macri, said the solution was “dialogue, dialogue and dialogue” and called for a clear message of shared responsibility.
But US President Donald Trump has already cancelled meeting Russia’s Vladimir Putin over Ukraine.
There is massive security for the summit in Buenos Aires, with a bank holiday declared for Friday and the city’s main business district shut down.
Protesters angry at the money spent on the summit while Argentina struggles through tough austerity demonstrated outside the meeting.
He is the only Arab leader in the G20 and already stood out in his traditional dress amid a sea of suits. And at times he looked uncertain, even nervous. Some of his counterparts shared a word or two but few went out of their way to shake his hand.
So the optics of the summit, to use the diplomatic jargon, were not that great for MBS.
What have the opening exchanges told us?
The world leaders were all called on to the stage and assumed their position for the traditional family photograph.
Saudi Crown Prince Mohammed bin Salman stood on the outside of the photo, far away from Turkey’s Recep Tayyip Erdogan.
After the photo was taken, the crown prince did manage a hearty exchange with Mr Putin.
French President Emmanuel Macron held a five-minute exchange with the crown prince during which, a French official said, Mr Macron had conveyed “very firm” messages over the Khashoggi affair.
In addition Mrs May held a 15-minute meeting to discuss trade with Mr Macri. Their two nations have long disputed sovereignty of the Falkland Islands.
Mr Macri’s opening address to the summit admitted there would be issues of disagreement that needed to be managed.
He called for consensus on sustainable development, the future of work, food supply, climate change and international trade, adding: “I am an optimist”.
What will go on on the sidelines?
There are certain to be plenty of bilateral, trilateral or even larger get-togethers, although the one that will not be taking place is the highest-profile.
Mr Trump said he would not meet Mr Putin because three Ukrainian vessels and 24 sailors seized by Russia in the Black Sea near Crimea had not been returned.
The key issue there will be the nations’ trade tariffs dispute.
The US has hit a total of $250bn (£196bn) of Chinese goods with tariffs since July, and China has retaliated by imposing duties on $110bn of US products.
China said consensus was increasing on a deal but that differences remained.
After earlier indicating pessimism on an agreement, Mr Trump said: “They want to and we’d like to. There are some good signs. We’ll see what happens.”
The Brics group, comprising Brazil, Russia, India, China and South Africa, issued a statement saying protectionism ran counter to the “spirit and rules of the World Trade Organization”.