Locally owned and operated in Honolulu, Hawaii, Core Group One, Inc. was established in July 2005 by Emi Anamizu and Jim Horiuchi to acquire Ogilvy & Mather Hawaii, Inc. Wanting to divest itself of the advertising business in Hawaii, WPP Group (the London-based parent company of Ogilvy & Mather) offered Emi and Jim the opportunity to purchase the company. Emi was the CEO and Jim was Creative Director at Ogilvy & Mather before the transition. Core Group One opened its doors on September 1, 2005.
In January 2013, Hendrix Miyasaki Shin joined Core Group One, bringing together best practices in branding strategy, creative services, account management, new/social and traditional media and marketing.