The Philippines: What stance towards Duterte?
Philippine President Rodrigo Duterte's anti-drug campaign has led to the summary deaths of thousands of suspected criminals at the hands of police and vigilantes since he took office on June 30.
The killings have been condemned by human rights activists and the Obama administration. The question now, former State Department officials say, is just what kind of a stand the Trump administration will take as he and his family balance their personal and financial ties with foreign policy demands.
Philippine developer Jose E. B. Antonio first met Mr Trump casually in the 1990s and has been his business partner in the Philippines for five years. Mr Duterte named him special envoy to the United States as the Philippines angrily pushed back at President Barack Obama for criticising his deadly campaign.
But Mr Michael H. Fuchs, until recently deputy assistant secretary at the Bureau of East Asian and Pacific Affairs, said he was deeply troubled by Mr Trump's overlapping priorities, particularly given the long list of globally significant issues in play with the Philippines.
These include planned joint military exercises in the South China Sea, the fight against militant Islamist groups based in the country's southern islands and the human rights abuses taking place.
"What we already have is a blurring of the lines between official and business activities," Mr Fuchs said.
"The biggest grey area may not be a President Trump himself advocating for favours for the Trump Organisation. It's the diplomats and career officers who will feel the need to, perhaps, not do things that will harm the Trump Organisation's interests. It is seriously disturbing."
India: Potential pitfalls in dual roles
In 2012, Mr Donald Trump Jr flew into Mumbai for a brief meeting with the state's chief minister at that time, hoping to salvage a residential tower representing the Trump Organisation's first planned project there. He was hoping the chief minister, Mr Prithviraj Chavan, would intervene on his behalf to get the permission needed.
The participants recall the meeting differently: Mr Trump's partner, Mr Harresh Mehta of Rohan Lifescapes, said development regulations had changed, leaving the project in limbo, and they hoped Mr Chavan could formalise a policy so the project could continue.
Mr Kalpesh Mehta, managing partner of Tribeca Developers, the Trump Organisation's development partner in India, disputed the claim by Mr Chavan that he had sought a special favour.
This example, analysts say, points to a potentially serious ethical hazard for a US president who is also a real estate mogul in India, with five projects under way.
One of Mr Trump's projects, Trump Towers Pune, is under investigation by local authorities after another builder alleged that one of its permits was fraudulent.
Another pitfall is that Mr Trump's partners in major projects are, in some cases, politicians themselves.
Turkey: Mixing business, politics and Islam
Turkish President Recep Tayyip Erdogan visited the 40-storey-high Trump Towers Istanbul after their completion in 2012, with Mr Trump and Ms Ivanka Trump appearing as part of the celebration the next day.
There is also the Trump Organisation's 2013 partnership with Turkey-based Dorya International, a luxury furniture maker of pieces sold under the Trump Home Collection.
The presidential campaign demonstrated how the goals of his business and political ventures can come into direct conflict, particularly when Mr Trump proposed barring Muslims from entering the US.
Calls were made to remove Mr Trump's name from the building. But Mr Trump's next move helped re-establish his standing. After a failed coup in Turkey in July, he defended Mr Erdogan's crackdown on dissidents. In between his two remarks, calls for the renaming of the Trump Towers ended.
Ms Jennifer Harris, who served on the staff of the National Intelligence Council and on the State Department's policy planning staff, said the twin hats that Mr Trump and his family would be wearing in Turkey would almost certainly complicate the jobs of US diplomats there.
Brazil: Hotel venture under probe
Mr Donald Trump Jr, the President-elect's eldest son, gushed with triumphalism when he announced a deal in 2014 to attach the family name to the Trump Hotel Rio de Janeiro, a lavish 171-room beachfront project.
Two years later, the venture is embroiled in a criminal investigation in Brazil, pointing to unfulfilled promises that are casting a pall over both the Trump business empire and the President-elect in their dealings in Latin America's largest country. The hotel officially opened for the Olympics but, months later, remains unfinished.
"Brazilian diplomats could try to avoid the problem of referring to the investigation when dealing with the Trump administration, but that's about all they can do," said Mr Maurício Santoro, political scientist at the State University of Rio de Janeiro.
"This is something that could hang over relations between the two countries for years."