Mr Wilson Lim has presided over 700 marriages, but one especially sticks in his mind. It took place in a hospital, between a dying man and his girlfriend.
Mr Lim was given just two days' notice, but he could not say no.
"They both were very brave. I'll remember it for life," the 49-year- old told The Sunday Times.
Mr Lim is not a religious leader or a Justice of the Peace. Instead, the real estate consultant is a Citizens Consultative Committee secretary in the Punggol East constituency and one of nearly 200 grassroots leaders who, since 1992, have been authorised to solemnise marriages.
Marriage numbers released by the Department of Statistics recently show that nearly 7,000 solemnisations last year, or about a third of the 22,540 non-Muslim marriages in the same year, were conducted by grassroots leaders.
This is about as many as the number of marriages conducted at the Registry of Marriages (ROM).
A spokesman for the Ministry of Social and Family Development, which oversees the ROM, said grassroots leaders have to be recommended by, for example, heads of religious orders or the People's Association before they can become licensed solemnisers.
The nominee must also meet strict criteria, he said, including having a track record as a community or religious leader, or other positions of influence or leadership.
Couples said grassroots leaders are a good alternative for solemnising marriages on weekends as the ROM is closed then, as well as on popular dates or if they are planning something "different".
Solemnisers said they have been called to conduct solemnisations on yachts, the beach and even at Jurong Bird Park, where the wedding ring was flown in by a bird.
For solemniser Tan Yan Boon, 46, who runs a vending solutions company, it can mean working his overseas business trips around dates requested by couples as early as one year in advance.
He has been married for 18 years and has three children, aged 17, 14 and 11.
While solemnisers can be officially booked only three months in advance, Mr Tan, who is a community club management committee chairman in Sembawang GRC, takes note of the dates and tries his best not to disappoint couples.
In nine years, he has conducted about 3,000 solemnisations. Almost all his weekends for the past five years have been spent marrying people.
He schedules up to two solemnisations a day, but tries to ensure that both are in the evening or in the afternoon so that he can have lunch or dinner with his family.
"The couples do keep me updated about their lives, inviting me to their baby functions," he said.
The solemnisers whom The Sunday Times spoke to all shared similar stories of friendship and giving love advice.
Ms Joanna Portilla, 45, who has been married for 14 years and has a nine-year-old son, has been a grassroots leader and solemniser for 10 years and has married about 1,000 couples.
"They are strangers first. Then we become friends on Facebook. Sometimes, it becomes a family thing and I marry the siblings too," she said.
She vividly remembers solemnising the marriage of a 76-year-old man and a 78-year-old woman who had been living together for 40 years.
"If you saw them together, you wouldn't have realised they didn't have any papers."
Mr Lim, who has been married for 20 years and has two daughters aged 13 and 15, said he advises couples not to tie the knot simply to get a Housing Board flat. He also tries to bring out their romance.
"I make sure they draft their own vows. When it is from their own heart, it's more meaningful," he said.