When organisers of the Trump-Kim summit scout for a venue, one simple but critical ingredient is a room with multiple doors.
Protocol dictates that President Donald Trump of the United States and Chairman Kim Jong Un of North Korea should not enter via the same entrance for their bilateral meeting - to avoid the perception that one arrived first and is "waiting" for the other.
This is just one of the many intricacies of hosting the June 12 summit, during which a sitting American president and a North Korean leader will meet for the first time since the Cold War that saw Korea split into two. On the table for discussion are, among other issues, a possible denuclearisation deal.
With such high stakes involved, the smallest detail can be sensitive and it is paramount that an appearance of parity be achieved, say past and present diplomats and protocol officers, as well as international relations scholars interviewed.
But they add that if any country can pull it off, it is Singapore, an old hand at organising other high-level events - including two historic China-Taiwan meetings in 1993 and 2015, the annual Shangri-La Dialogue and Asean meetings.
Singapore's role, as host, is "to provide a peaceful, safe and conducive environment for the summit", Ambassador-at-Large Ong Keng Yong tells The Sunday Times. "The host should also be ready to provide any other assistance as requested by the two sides, provided that this is within the ability of the host to provide," he adds.
What Singapore offers is a backdrop, say those interviewed. "It is not our meeting nor our show," says Mr Nicholas Fang, director of security and global affairs at the Singapore Institute of International Affairs. As one former Ministry of Foreign Affairs (MFA) diplomat, who declined to be named, quips: "We only provide the tea and coffee."
PLANES, CARS AND COFFEE
But serving tea and coffee is not as simple as it sounds.
No detail is too small. For one thing, that coffee.
Many foreigners are not used to the local Nanyang coffee, notes a retired MFA protocol officer with a smile. An international brew has to be served instead.
Many other behind-the-scenes considerations have to be thought through, from security to logistics to ensuring - as Dr Alan Chong of the S. Rajaratnam School of International Studies (RSIS) puts it - "an atmosphere of visible equality".
"It is a complex operation and we should salute our officers who are dealing with the preparations," says Mr Ong, noting that multiple ministries and agencies will be involved. These include the Foreign Affairs, Home Affairs, Defence, Communications and Information, and Transport ministries and agencies.
Dr Graham Ong-Webb of RSIS notes that Singapore is taking charge of the form and not the substance of the summit - but added that the form can be very important, as it ensures that "on an emotional, psychological and mental level, the people doing the discussing are in the best possible setting".
"Protocol can make or break summits," he adds.
This is why, prior to the summit, there will be discussions between Singapore and both parties, "which would allow us to better understand the situation, including possible sensitivities", says Mr Ong.
With just a week left before the meeting, such preparations are now in full swing.
The need for Singapore to foster an air of equality between the two visiting leaders begins the moment their planes land, says Dr Chong. If President Trump's Air Force One looks much more impressive than the plane Chairman Kim arrives in, the Koreans may insist the press not be allowed to cover the airport arrival. The journalists could then be invited to only the official reception at the Istana.
The cars they ride in must also be equally dignified. The Americans bring their own cars along on their overseas trips - including the armoured presidential "The Beast", a Cadillac. The North Koreans, meanwhile, may have to rent from a local company cars that look comparable to the American sedans.
Based on diplomatic convention, each of the two leaders will be accompanied by a Singapore Cabinet minister during the trip.
The importance of parity is also why, despite initial chatter of the summit taking place at Marina Bay Sands, this is unlikely to happen, says Dr Ong-Webb. It is owned by American magnate Sheldon Adelson, a friend of President Trump. Holding the meeting there could compromise the air of neutrality and equality, he says.
Also, neither leader should stay at the summit venue - again, so nobody is seen as a host receiving his visitor. For now, word is that President Trump may stay at Shangri-La Hotel and Chairman Kim could stay at The Fullerton Hotel - with the summit likely to be held at Capella Hotel or another hotel on Sentosa.
Also potentially contentious is the question of who gets a seat at the main table for any banquet. The retired protocol officer says he once saw a round table set up to fit 36 guests - to avoid disagreements.
He added that the South Korean media has been known to publish complete graphical guides on who is sitting where at such banquets.
Such details will be important in this summit, given Singapore's longstanding ties with the US.
Mr Fang says: "Singapore's relationship with the US is ostensibly broader and deeper than its ties with North Korea, but it cannot be seen to give preferential treatment to any party."
The North Koreans may be especially sensitive, says Dr Ong-Webb. North Korea is frequently treated as a rogue state and often finds itself having to "negotiate its sovereignty" on the international stage. As host, Singapore succeeds if the North Koreans feel respected here, he adds.
NEED FOR PLANS B, C AND D
Another reason Singapore was chosen as the venue for the summit is its tight security, say analysts.
Singapore is known for its good border security and its ability to lock down meeting venues, says Dr Ong-Webb. He cites the case of a Gurkha officer shooting dead a driver who failed to stop at a checkpoint during the Shangri-La Dialogue in 2015. For security experts, this case provides further evidence that security here is "rock solid".
That said, nothing can be guaranteed as security involves unknowables, says Dr Inwook Kim, an international relations expert at the Singapore Management University.
The retired protocol officer says many foreign leaders bring along their own armed security personnel. They must declare to Singapore the arms and ammunition they carry, and will be issued a certificate after being informed of local rules of engagement. Singapore usually assigns armed officers to shadow them throughout the trip.
Defence Minister Ng Eng Hen yesterday confirmed Singapore will bear the security costs of the summit, adding: "It's a cost we're willing to bear to play a small part."
Finally, the smooth running of a summit also involves clockwork precision logistics.
Leaders must not be made to wait in awkward silence - especially if the press is in view, says the retired protocol officer. One trick of the trade is to place them in holding rooms. Once ready, they will enter the meeting room at the same time.
Another challenge of this summit is accommodating the international press contingent, which is likely to be huge, adds Dr Kim.
Most summits of this magnitude are planned six months to a year in advance, analysts note. But this one is being put together in weeks.
"There are also numerous international events taking place (at this time), including the Shangri-La Dialogue," says Mr Fang. "It would be fair to say... there is a fair amount of pressure and apprehension among all the stakeholders involved."
But having hosted other sensitive events, Singapore officials would be attuned to the need to "take into consideration a full spectrum of factors", he adds.
That said, one risk for Singapore is if the summit ends with no agreement, says Dr Chong. The two sides may, in addition to pointing fingers at each other, want to place some blame on the host, he adds.
Another potential complicating factor: There have not been regular state visits between Singapore and North Korea - so officials may be less familiar with one another. But Dr Chong notes that there is a North Korean embassy here, so there would be some level of interaction.
One last variable that could throw a spanner in the works: the unpredictable personalities of President Trump and Chairman Kim. They may - say, as a negotiating tactic - refuse to stick to a pre-agreed itinerary, says Dr Chong.
"This will challenge the most well-rehearsed protocol. The Singapore officials will just have to play by ear. They must have not just Plan B, but Plans C and D as well."
Other landmark meetings Singapore hosted
WHY IT WAS HISTORIC
Singapore hosted a meeting between Chinese President Xi Jinping and then Taiwanese President Ma Ying-jeou in 2015. It was the first such summit since the Chinese civil war reached a stalemate in 1949. The meeting symbolised closer China-Taiwan ties, though no agreements or joint statements were made.
WHY IT WAS SENSITIVE
The summit marked a delicate balancing act for President Ma, whose Kuomintang (KMT) party is friendlier to China, but which has to stay mindful of a growing desire among younger Taiwanese for more distance from the mainland.
The meeting also happened two months before Taiwan's presidential election, with KMT trailing the pro-independence Democratic Progressive Party.
Three members of an anti-China party from Taiwan who wanted to protest here were questioned by Singapore police.
The Chinese delegation stayed at St Regis Singapore, while the Taiwanese delegation stayed at Four Seasons Hotel. The summit was held at Shangri-La Hotel.
The two leaders began the summit with an 81-second handshake, witnessed by 600 journalists. They adjourned to another room for public remarks, followed by a closed-door meeting.
As the two sides had not officially recognised each other, the leaders addressed each other as "Mister" and not "President".
The two leaders later held separate press conferences.
At dinner, each side brought famous spirits - Mr Xi's from Guizhou province, and Mr Ma's from Kinmen and Matsu, islands occupied by Taiwan since 1949.
The bill for the summit venue and the meal was split equally down the middle - an outcome of pre-summit negotiations.
WHY IT WAS HISTORIC
The 1993 Koo-Wang talks were the first public meeting between China and Taiwan since the end of hostilities in 1949. Four agreements were inked, marking a new era of cooperation. The two sides, technically still at war, pledged to deepen business and cultural ties. They were represented by semi-official groups: China's Association for Relations Across the Taiwan Straits, led by Mr Wang Daohan, and Taiwan's Straits Exchange Foundation (SEF), led by Mr Koo Chen-fu.
WHY IT WAS SENSITIVE
Mr Koo nearly resigned ahead of the meeting, as Taiwan's opposition sought to discredit him by branding his family traitors during the Japanese Occupation.
The opposition was strongly opposed to reunification, which the Taiwan government said was not on the agenda. But Mr Wang caused a stir when he said just before the talks that "there is nothing we cannot... talk about".
On the opening day of talks, 12 opposition Taiwan legislators came to challenge the SEF's right to represent the Taiwanese.
More than 200 journalists were in Singapore to cover the three-day event held at the NOL Building in Alexandra Road.
Much thought went into ensuring parity between the two sides.
Four copies of the pacts were made: two in the traditional Chinese script running vertically, which is used in Taiwan, and two in simplified Chinese running horizontally, as used in China.
The agreements also indicated the month and day of signing, but not the year, as the two sides used different calendars.
Mr Koo and Mr Wang also swopped seats midway through the proceedings, due to a custom that considers the person seated on the right to be more senior.