WPP's Geometry Global has named Jon Hamm to the newly created post of global chief creative officer. Geometry was born last June from the merger of G2, OgilvyAction and JWTAction, agencies specializing in shopper, relationship, promotional and experiential marketing.

Mr. Hamm, who will begin Nov. 3, had been global chief creative and innovation officer at Interpublic Group's Momentum Worldwide. He joined IPG in 2008 when Greenroom Digital, the London-based digital agency he created in 2000, was acquired by Momentum.

During his time at Momentum, Mr. Hamm helped the agency expand its digital, technology and content offerings. One of his better known projects was the American Express "Unstaged" series -- a digital branded music program.

Mr. Hamm will report to Geometry CEO Steve Harding. "Although it's a new role, the intention last year, when Geometry was in its planning phase, was always to have a global chief creative," Mr. Harding said. "The challenge has been trying to find the right person that matches what we were looking for to carry out the creative agenda."

The agency's work, he explained, "uses data and insights to drive our agendas and drive a better creative product."

As an activation agency, in industry jargon, Geometry is "primarily focused on inspiring people to buy," Mr. Harding said. But his team is aiming to "redefine activation," he said, saying the field hasn't historically been sufficiently creative or strategic.

Clients are also increasingly looking for an international perspective, Mr. Harding added. In his new role, Mr. Hamm will be working with Geometry's regional directors to develop appropriate creative products.

The merger that formed Geometry, where clients include Kimberly-Clark and Unilever, brought together key elements to do great creative work on a large canvass, Mr. Hamm said. "It has that scale as well as balance between art and science and balance between strategy and creative," he said.