“They remain a big out-of-bounds area for procurement people but this has been changing in the past five years,” he said.

The present squeeze on corporate finances means purchasers will be increasingly asked to engage with a whole range of marketing services agencies, said Williams, who will be a director on the newly created board at QP Group.

Agencies have a perception that purchasers “are their client’s KGB officers with an array of sinister tools and techniques”.

Williams said this will have to change if successful relationships are to be established, but it will be up to both sides to break down these stereotypes.

Williams, CIPS president in 1999-00, took the manufacturing route to procurement and began his purchasing career in 1978 at Rover.

In 1984, he moved to British Airways and in 1994 joined WPP, the world’s largest provider of marketing services, as director of group procurement. At the company, he has been increasingly drawn into advising WPP’s account managers on how to deal with the purchasing managers of their clients. “The WPP executives wanted to know who these people were and what their role was,” said Williams.

At QP Group, Williams aims to build up a specialist marketing services resource that will operate around the world.

He said: “It could take many years for a procurement department to build up effective relationships with their marketing colleagues and suppliers.

“We will offer proven processes and specialist market knowledge to shortcut this process and deliver fast-track, change.”