Year after year donations are collected, from schools, clubs, companies and generous individuals, in a series of fund-raising events that boost the season's festive atmosphere. With cash from OSC, small charitable organisations have expanded and thrived, helping more and more people in need.

"Christmas is a time for giving, a slot in the calendar where people are feeling generous," says Alastair Monteith-Hodge, who organised the campaign in its first year, 1988. He was an RTHK radio presenter and producer at the time, and is now chief executive of the Children's Cancer Foundation. Operation Santa Claus' roots date back to the 1960s, Monteith-Hodge says. The tradition started with RTHK Radio 3 presenters performing public stunts to raise funds for charity. They dived into Victoria Harbour in the winter cold, read poetry on roofs and climbed flagpoles among other capers.

RTHK's current deputy director of broadcasting, Tai Keen-man, recounts the stories with relish. "Our popular DJs and presenters gathered at Queen's Pier. When donations reached a certain amount, they would jump into the sea," he says.

Santa Claus was played by the inspector of prisons, David Hampton. A fluent Cantonese speaker, he played the same part for the Children's Cancer Foundation in the 1990s, growing his beard from September to December just for his Santa role.

The early campaigns stopped in the 1970s, when the launch of the Community Chest gave Hongkongers an official body to receive charitable donations. "Perhaps people were asking, 'Why did we have all these crazy gweilos doing these things when we have the Community Chest?'" Monteith-Hodge says with a chuckle.

The late 1980s brought worries about the future of Hong Kong, after the Sino-British Joint Declaration was signed.

"The mood in society was quite down," Tai says. "Maybe people thought it was time to conduct a charity project to cheer up society."

Tony Baynes, the head of RTHK Radio 3 at the time, asked Monteith-Hodge to "resurrect" Operation Santa Claus in 1988. "Our aim was to raise awareness for small charities and their missions, and raise funds for them. The radio was a good way [to do it]," Monteith-Hodge says

They identified Watchdog, a learning centre for children with special educational needs, as their target charity that year, and set out to raise HK$100,000. In the end they went slightly over the top, reaching HK$101,000.

Fundraising events included the pantomime, a British Christmas tradition, which gave men a chance to do outrageous things, including dressing up as women. On one Christmas radio show, audiences donated money to sponsor the playing of a hit song from the year. "We had entertainment to make expats feel like it was Christmas back home," Monteith-Hodge recalled.

Another event was the Battle of the Taipans, in which real taipans - bosses of big companies - were challenged in a general knowledge quiz. "It was fun, but the fundraising was serious," Monteith-Hodge says.

In 1989, the campaign's target was increased to HK$150,000, with the chosen charity the Children's Cancer Fund (now called the Children's Cancer Foundation), which had been established that year.

One day, Philip Crawley, the 's editor-in-chief at the time, gave Monteith-Hodge a call and says: "Let me know if there's anything I could do to help," to which the radio man replied: "Can you give us half a page on page three in the paper every day for a month?"

Crawley almost immediately agreed to the request. "And that was it," Monteith-Hodge says. "I put down the phone and there was panic. 'What are we going to do with half a page on page three every day for a month?'"

Every December since that year, the has been publishing beneficiaries' stories and giving coverage to fund-raising events. "Boy, it just took off," Monteith-Hodge says. "Now it was not just on radio. It was a multimedia campaign, a very powerful combination."

An avalanche of cheques came in every day, and the fund-raising target of HK$150,000 was passed in the first week, he recalls.

Meanwhile, the Operation Santa Claus "Christmas tree" progress chart began appearing on page three of the , keeping track of the donations rolling in.

Shortly before Christmas that year, RTHK outdid itself by holding a live, outdoors OSC broadcast near the Tsim Sha Tsui Star Ferry pier. There were toys, Christmas puddings and a lucky draw for a gold coin. And of course, there was Santa Claus.

"We broke the million dollar barrier that day. It was just amazing," Monteith-Hodge recalls.

By 1990 the formula was in place, and the campaign grew bigger and bigger. Over the first 15 years, only one or two beneficiaries were picked each year. Then in 2003 the number of charities receiving support from OSC jumped to 12, chosen from the hundreds of suggestions put forward by readers and listeners.

Current editor-in-chief Wang Xiangwei says: "It allowed a variety of different charity groups to benefit. OSC has grown over the years to reflect the different needs in society. It's amazing to see how people still give generously during times of economic uncertainty."

Another milestone achieved that year was the amount raised - HK$6.5 million, almost double the previous year's figure.

But 2003 was also a sad year for Hong Kong, as the Sars outbreak killed 299 people in the city. Bryan Curtis, head of English programming at RTHK, says: "Towards the end of 2003, people felt we were turning the corner. There was a lot of relief in the community. People gave from their hearts."

Operation Santa Claus was turned into a registered charity that year, with the formation of SCMP Charities Ltd. Major donors were included on the selection committee, which chooses each year's aid recipients. The next year, 2004, donations shot up even further, to HK$7.2 million for the campaign and another HK$9.6 million for victims of the South Asian tsunami.

Curtis noted a new trend of donors organising their own fund-raising events for the OSC campaign, in some cases with a high degree of creativity. One chief executive jumped off Macau Tower and asked his employees to donate, a bit like a revival of the "crazy stunts" of the old days, he says.

As the campaign developed over the years, donors have become more engaged, Curtis says: "Donors are more concerned, now, about seeing their money at work." With the coverage given to beneficiaries' stories, "people feel they can see it, touch it and taste it", he says.

Cliff Buddle, the 's special projects editor, says meeting beneficiaries and seeing their project updates was one of the most rewarding times for him. "You really see how OSC changed people's lives."

The campaign has continued to broaden in a way that organisers might not have foreseen 25 years ago, Tai says: "Donor-beneficiary relationships have extended to outside the campaign, giving continuous support to the charitable organisations."