The appointment of the former spokesman for the Prime Minister reflects the importance the tour will hold in the 2005 sporting calendar and the level of media attention it will attract.
Lions head coach Sir Clive Woodward, who has met Campbell on a number of occasions, said: "A Lions tour is a massive media event. There will be a huge level of interest from the travelling media, the fans who will go out in their thousands and the New Zealand public.
"We need to have the strategy and processes in place to deal with the pressures that will bring.
"Alastair will act as an advisor both in the build up to and on the tour itself. His role is to work closely with not only myself but also (tour manager) Bill Beaumont, (media manager) Louisa Cheetham and (team manager) Louise Ramsay."
The Lions media strategy will be aimed not just at ensuring the British, Irish and New Zealand media can cover the tour effectively, but also at meeting the needs of rugby fans on the tour and at home.
Campbell said: "With rugby attracting more media and public attention than ever, this tour will be one of the great sporting events of 2005, and I hope I can contribute to the planning and preparation, and to ensuring the media and public get the most out of the tour itself.
"I am looking forward to working with management and team as a strategy is put in place, and to going out for the later stages of the tour."