The company, which has 7000 offices worldwide, has appointed the AAR to handle the pitch. It has already contacted several agencies around the world, including the UK, with meetings taking place this week.
A spokesman said that Adecco, which is based in Switzerland, is looking to appoint its first global agency to find 'ways to strengthen its core brand'.
Earlier this month, Adecco promoted Ian Grundy, senior vice-president of marketing communications and international sales for Adecco USA, to the position of senior vice-president of public relations and global marketing partnerships.
Grundy reports to Adecco's chief marketing officer, Gonzalo Fernandez-Castro, who is based in Zurich and is overseeing the global review.
Rival Manpower appointed WPP's Grey and Red Cell to handle its global brand advertising in July following a pitch against Young & Rubicam and Lowe. It is planning a £20m campaign that will break later this autumn.