Olympics chief Thomas Bach urged delegates to seize the chance for change Thursday and approve a wide-ranging revamp of the games likely to include a shake-up of the sports contested and a new TV channel.
Bach was addressing about 1,000 representatives at the Association of National Olympic Committees general assembly (ANOC) in Bangkok, ahead of the release of 40 proposals which will be voted on next month.
"The time for change is now. It is not the time to start the discussion again and again," the International Olympic Committee (IOC) president said.
"We have been discussing for one year... now is the time for agreeing on something."
IOC delegates will learn the full detail of the proposals in two days time and they will be published next week before being put to a vote at the IOC's extraordinary session in Monaco on December 8.
"We have to take this opportunity now to drive these changes. Now we are sitting in the driver's seat of the bus," said Bach.
"If we don't make these changes now, others will drive this bus and we will have to sit on the back seat of the bus and have to hope that the driver is going in the right direction."
Measures under discussion include a year-round digital TV channel and an end to the limit on the number of sports contested, with host cities also able to propose sports.
Hosting bids will have to focus on the event's legacy to each city. The revamp is also aimed at putting the focus on athletes and youth, and improving the IOC's organisation and structure.
Bach, who has ambitions of placing the Olympics at the heart of modern "society" -- a word he mentioned some 20 times -- said the time was ripe for a makeover after successful Games at London and Sochi.
"The reason to change is because we are successful, because if you don't change when you are successful, the time will come and will come very fast when you are forced to change," he said.
"We can already see some challenges on the horizon... if we miss this opportunity, then the window of opportunity will be closed."
The 204-member ANOC is an umbrella grouping of the world's national Olympic committees led by the influential Kuwaiti Sheikh Ahmad Al-Fahad Al-Sabah, who also heads the Olympic Council of Asia.