US President Donald Trump and his Chinese counterpart Xi Jinping have been at odds over a range of issues since the billionaire businessman took office in November.
As the two leaders prepare to meet face-to-face for the first time at Trump's luxury resort in Florida this week, these are the topics likely to top the agenda.
Even before North Korea's ballistic missile launch on Wednesday, Pyongyang's nuclear weapons programme was always going to dominate the Trump-Xi summit.
The North is economically reliant on its sole ally Beijing, and Washington has long pushed China to use its leverage to punish the hermit state.
While China has shown growing impatience with its neighbour's bad behaviour, Beijing is reluctant to push the country too far for fear that the regime might collapse, unleashing a flood of refugees across the border.
Late last month, in a warm-up to this week's meeting, Trump Tweet-lashed China for doing "little to help" rein in Pyongyang and he has since warned the US is prepared to go it alone in bringing the North to heel.
During the presidential campaign, Trump repeatedly bashed China for its "unfair" trade policies and accused it of artificially depressing its currency to give its exports an unfair advantage.
Since taking office, he has often returned to the theme, warning that he will slap the world's second-largest economy with massive tariffs if it does not increase US access to its markets.
In a tweet last week, he highlighted China's massive trade imbalance with the US - over $310 billion last year - as a serious problem that could make his upcoming talks with Xi "difficult".
But Trump has also hinted at his willingness to use trade issues as a bargaining chip to secure more cooperation from China on North Korea.
China has its own wish list, including fewer restrictions on exports of sensitive US technology.
Trump infuriated China by taking a protocol-breaking phone call from Taiwan President Tsai Ing-wen and suggesting he might break from the US's long-standing One China Policy, which nominally acknowledges the Asian giant's claims over Taiwan without recognising them.
The situation cooled down after a conciliatory phone call in February with Xi, where Trump walked back his comments.
The move seems to have placated Beijing, but it left many in democratically ruled Taiwan wondering if the brash billionaire might use their home as a bargaining chip.
South China Sea
China's claims to most of the South China Sea and its controversial moves to build on disputed islands and reefs in the area, including installing military facilities on some, have drawn strong criticism from Washington.
Several of Trump's cabinet, including Secretary of State Rex Tillerson, have warned Beijing against throwing its weight about in the region, insisting the US would intervene if necessary to preserve international rights of navigation.
Human rights have been a long-standing point of conflict in Sino-US relations.
When Trump took office, many Chinese dissidents thought he might be willing to take a hardline against Beijing on the issue.
But the president - who praised China's handling of the Tiananmen Square crackdown in a 1990 interview - has so far demonstrated little interest in the issue.
The White House has said the topic will "continue to be brought up in the relationship", but human rights activists are worried the Trump administration has already missed several opportunities to spotlight Beijing's abuses.
Without US pressure, they argue, the problems will only worsen.