Unwanted London 2012 Olympic Games tickets bought in the original ticket lottery will go on resale from 6 January, giving sports fans another chance to go to the world's biggest athletics competition.
They're being sold through the London 2012 ticketing website until 3 February.
Sellers will receive face value for their tickets.
The London Organising Committee of the Olympic Games and Paralympic Games (Locog) is hoping that reselling unwanted tickets will prevent empty seats at the events.
Those wishing to sell their tickets can do it via their ticketing account.
Unsold tickets will remain with the original ticketholder, though Locog says there will be another resale opportunity some time in April.
Ticketholders are also being warned not to sell their tickets outside of the official London 2012 system without permission from Locog, else face criminal charges.
Tickets for the Olympic Football Tournament and the Paralympic Games are on sale until 6 February. Any unsold tickets will be re-opened for sale in Spring.
"I'm convinced that most people will want to hold on to their tickets," said Locog CEO Paul Deighton when announcing the resale in December.
"But we are pleased to offer this resale programme which will give those who wish to use it an opportunity to securely sell their tickets to others who wish to go to the Games or purchase more tickets and help us to achieve our aim of having full venues."
A recent administrative bungle from Locog saw 20,000 tickets being sold for a synchronised swimming event, despite there only being 10,000 seats.
They put it down to "human error" and are offering those left missing the event a chance to get tickets for another event, including the prestigious men's 100m final.
The 10,000 tickets will come from a pool of 1.3million tickets left, which are due to go on sale in April on a first-come-first-serve basis.