Barraclough will remain at the agency until July and, according to a statement from the agency, he is currently "exploring a number of options both inside and outside the Abbott Mead Vickers Group".
In a statement issued by Proximity, Barraclough said: "It's been an amazing 12 years, but it is time now to move on. I am immensely proud of the agency we have built and of the team at Proximity London. I am leaving at the right time with agency's star very much in the ascendancy."
However, industry sources have suggested that Barraclough has had enough of the big agency network structure and wants to get back into small agency culture. It is understood he is looking to set up a pure direct marketing agency with his creative partner Steve Edwards.
Barraclough set up what was Barraclough Hall Woolston Gray in 1991 with Simon Hall, Elly Woolston and Duncan Gray. Hall is now chief executive of the agency, Woolston is deputy chairman and Gray is executive creative director.
In 1999, Barraclough became the agency's chairman, relinquishing responsibility for the day-to-day running of the agency and management of the creative team.
Although he has continued to write compelling and award-winning creative copy for the agency's biggest accounts, including Volkswagen and Alliance & Leicester, responsibility for the creative department was handed to Caitlin Ryan and Kim Woodrow, until Woodrow was replaced by Warren Moore last year.
Hall said: "Having worked with Chris for such a long period of time, I will certainly miss him. It will be strange not seeing him on the seventh floor. However, life goes on and Chris leaves behind a creative department that is in the best shape it has ever been."
BHWG was rebranded Proximity London in 2001, following its merger with Clark Hooper and Traffic to create an agency providing CRM, direct marketing, data, media, promotions, trade marketing, design and branding, events and interactive services.
Proximity London is part of Omnicom-owned network AMV Group and employs 300 staff.
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