Is military intervention likely in Gambia?
It is possible. Overnight talks, by Mauritanian President Mohamed Ould Abdel Aziz and other African officials, failed to convince Gambia's Yahya Jammeh to step down.
The regional bloc, the Economic Community Of West African States (ECOWAS), made up of 15 nations, has instructed Senegal to lead the offensive into Gambia.
Senegal has deployed hundreds of troops along its shared border with Gambia and has threatened to invade if Jammeh does not peacefully hand over power. Regional power Nigeria has deployed a warship off the Gambian coast and its aircraft are now stationed in Senegal.
Barrow won about 45 percent of vote in elections held in December.
Why is Jammeh refusing to step down?
He is contesting the election results in the Supreme Court and wants the country to wait for the decision.
Jammeh was due to leave office on Wednesday, ahead of Barrow's inauguration on Thursday.
However, on Tuesday, Jammeh, Gambia's leader since 1994, declared a 90-day state of emergency, saying it would “prevent a constitutional crisis and avoid a power vacuum”. Jammeh, who seized power in a military coup, said foreign powers had interfered with the election results.
Will Barrow still become president?
The president-elect tweeted that he will be sworn in at the Gambian embassy in Senegal's capital Dakar on Thursday.
His inauguration was due to take place at the National Stadium in Bakau, which is west of the capital but due to safety concerns, he has remained in Senegal.
My dearest Gambians — the presidency of Yahya Jammeh is officially over. The new era of Gambia is here at last. #NewGambia
— Adama Barrow (@adama_barrow) January 18, 2017
Is Jammeh's party supporting him?
Gambia's Vice President of twenty years, Isatou Njie Saidy, quit on Thursday. He is the latest in a series of high ranking officials to abandon Jammeh's camp.
Some members of his 'Alliance for Patriotic Reorientation and Construction' party have stayed on.
The foreign affairs minister, along with the ministers of finance, trade and environment, have all resigned. The information minister has gone into exile in Senegal.
If Jammeh initially accepted the election result, why did he backtrack?
He rejected the election results after the electoral commission admitted some errors.
The commission, however, insisted the errors did not affect the final outcome.
Jammeh then lodged an objection with the Supreme Court. The court can only hear the matter in May because of a shortage of judges.
Last week, he filed an injunction to stop the chief justice from swearing Barrow into office. On Monday, the chief justice recused himself and said he could not rule on the matter.
You are the elected president of the Gambia and I wish you all the best. My time is up.
- Yahya Jammeh told President-elect Adama Barrow in a call immediately after the election results
How are Gambians reacting?
Thousands of people are fleeing, crossing the border into Senegal and Ginuea. People are queuing at bus and ferry stations in the capital fearing civil unrest. Some are heading to rural towns.
The UN High Commissioner for Refugees (UNHCR) said 26,000 people have fled so far, mostly women and children. Heavily armed security forces have set up checkpoints across the city.
Others are taking precautions, stocking up on food and supplies. Roads are quiet and street vendors are notably absent.
Thousands of tourists have been evacuated by holiday companies and travellers are advised to avoid the region.
The vote against Jammeh was a "rare show of defiance" for citizens. Human rights groups called Jammeh one of Africa's most capricious and ruthless autocratic leaders, who has resorted to torturing and killing opponents.
If Jammeh continues to cling onto power, Gambians are concerned he may target those who opposed him. Many have taken to Twitter, using the #jammehmustgo:
#JammehMustGo Africans must unite against Leaders who wants to stay in office more than necessary
— Jibril (@JibrilSeze) January 8, 2017
— NanaOnyinahBa (@PRGirl233) January 19, 2017
Tension is high, Thousands of people have fled to neighbouring countries, fearing violence may erupt. Let's Pray for #Gambia fellow Africans
— Atanas (@atanasi_) January 19, 2017