London - Rugby enthusiasts have been warned to buy tickets for next year's Rugby World Cup through official channels or risk being refused entry to matches.
The championships begin in England in September.
Up to a million tickets will go on sale at 09:00 GMT on Friday - 300 000 have already been sold via rugby clubs - and fans have until 29 September to apply.
However, with demand for tickets in Britain expected to be second only to the London 2012 Olympics, there is a growing fear that organised touts could hijack the process.
Unlike the ticketing system for the London Olympics, in which the government introduced legislation banning the unauthorised resale of tickets, the International Rugby Board (IRB) did not apply for the same conditions.
England Rugby 2015 subsequently failed to persuade the government to make touting of World Cup tickets illegal and are hoping that their terms and conditions that forbid anyone buying a ticket from an unauthorised outlet will dampen the market.
In a bid to deter touts, ticket agency Ticketmaster has implemented software that can detect multiple applications but officials accept that they face a difficult battle against increasingly sophisticated operators.
"Fans should only buy through official sources," said England Rugby 2015 communications director Joanna Manning-Cooper, who saw the benefit of legal protection during her time with the London 2012 Olympics organising committee.
"We are doing everything we can to make sure tickets get into the hands of fans who want to come to the tournament and not to touts who simply want to sell them on at a profit."
The tournament has to raise £250m from tickets and organisers have implemented a wide range of prices.The 20 participating countries will play across England and Wales with Wembley, the Millennium Stadium, Elland Road, Villa Park and London's Olympic Stadium among the venues being used.
The tournament begins on 18 September next year when England play Fiji at Twickenham.Champions New Zealand, who beat France 8-7 in the final in Auckland in 2011, begin their defence against Argentina at Wembley on 20 September.