The appointment comes in the same week that the Office of Fair Trading has announced it is to launch an investigation into the concentration of buying and selling points in the sector.
Baker replaces Alan James and will report into OAA chairman Jeremy Male.
He joins the OAA on 24 May and will be responsible for helping transform the OAA into a more marketing-led trade body.
He is a former European marketing director for Viacom Outdoor and left CBS Outdoor last year where he held the role international marketing and development director. Most recently he was managing director of Media by Permission, a CRM system for the media industry
Male says: “We are now moving into a new phase where the OAA needs to be more on the front foot and communicate the benefits of the out of home medium as powerfully as possible. Mike’s wide media expertise and marketing skills will be fundamental to the way we want to develop the OAA’s external profile over the coming years.”