The serious business of the G20 is getting under way in Osaka, with world leaders sitting down to group meetings.
Already differences are starting to show between the US and China, however.
The Trump administration has banned the use of technology from Chinese technology giant Huawei in critical US infrastructure, to the disapproval of Beijing.
During the first session on the governance of digital products, Chinese President Xi Jinping said that countries couldn't develop "behind closed doors."
“As effective data governance should not only facilitate the collection analysis application and flow of data but also respect the right of self management for all countries," he said.
But US President Trump's opening remarks underlined the need to "ensure the resilience and security of our 5G networks."
"This is essential to our shared safety and prosperity," he said.