Donnelly began his career as a junior writer at Barraclough Hall Woolston Gray under the agency's founder and then creative director Chris Barraclough. Holbrook started out at Clarke Hooper under Warren Moore.
The pair were brought together in 2001, when Clark Hooper was merged with BHWG to create Proximity London as the UK arm of the Omnicom-owned below-the-line network.
The move to Partners Andrews Aldridge follows a successful year for the team, during which time they won a series of gongs at the DMA Awards.
They picked up a gold in the multimedia category for work on TV Licensing and a silver for their student TV licensing campaign in the acquisition section. They were also part of the team that won the silver award for CRM strategy for Persil. Other campaigns they have worked on include BTopenworld swear box promotion.
"We've always admired the creative work coming out of Partners Andrews Aldridge, and we're joining at an exciting stage in the agency's development," Holbrook and Donnelly said.
The agency's creative department is headed up by creative partner Steve Aldridge, who co-founded the agency with Phil Andrews in 1998.
"I am delighted to have such a talented award winning team joining the agency. I believe they will make a huge impact on our work helping to take our creative product to the next level," Aldridge said.
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