A former Microsoft executive and several other Irish entrepreneurs are making a foray into the €120 million outdoor advertising market with the creation of a new company, Fourth Edition.

Ann Riordan, formerly country manager for Microsoft Ireland, Eddie Kerr, co-founder of directory enquiries group Conduit, and Martin Barry, one of the founders of the Bus Media advertising group, have come together to challenge Clear Channel, JC Decaux and Viacom for the Republic's main advertising contracts.

The Irish outdoor market, which grew by almost 11 per cent between 2004 and 2005, is dominated by several global players.

One of those, US group Titan, has recently increased its presence here through the purchase of UK group Maiden Advertising. The acquisition propelled the group into second position in the market and gave it the Republic's largest advertising contract, the CIE. Clear Channel holds the contract for advertisements on Dublin bus shelters.

Fourth Edition was founded earlier this year with funds provided by five of the group's six directors. Martin Barry, the managing director and founding member of the group, declined to say how much money was being put into the venture.

The company was previously known as Kerbside Media and on its website claims to have more than 40 years experience in managing out-of-home advertising campaigns. Its existing sites include pitchside advertising in Tallaght, Coolock, Celbridge and UCD as well as the National Hockey Stadium and its clients include Smart Telecom and Coca Cola.

Also on the board are David Coleman, the group's sales director, Declan McCourt, a non-executive director and chief executive of OHM Group, and Richard Hall, also a non-executive director.

The outdoor advertising market accounts for about 8 per cent of the total advertising space in Ireland.