The matchmaking company has hired Tina Fegent, the former Lowe London commercial director, to head the new division.
Fegent, who has also worked at Grey London as its commercial director, will initially provide advice for new and established client/agency partners when they are negotiating costs.
The division will also provide training for marketing and procurement teams and agencies.
The AAR claims that a number of unnamed clients are lined up to start using the service when it launches later this month.
Fegent has previously worked on both the client and the agency sides of the business. She set up and ran the marketing purchasing teams for O2 and GlaxoSmithKline, before being hired by Garry Lace, the then chief executive of Grey, in 2003. He hired her again at Lowe when he moved there two years later. In her most recent role, as the global head of marketing purchasing for France Telecom Group, Fegent oversaw the company's global creative and media business reviews.
Kerry Glazer, the AAR chief executive, said: "We are delighted to have secured Tina Fegent as our new head of procurement consultancy. The launch of our procurement consultancy will focus on the AAR's core strategy, which is expert advice together with an appreciation of agencies and clients."