At Addiction Worldwide, Peyton will work across all the agency's disciplines including TV, print and outdoor advertising, digital, social media and brand engagement.
Peyton, who has been at ISBA for the past six years, was responsible for more than 300 pitches across the world. She handled relationships with direct, integrated and digital agencies.
Jeremy Rainbird, chief executive of Addiction Worldwide, said: "We're thrilled to be bringing Christina on board. Addiction has a truly unique offering and she's going to play a key role in communicating that."
Peyton said: "Having spent the last six years working with clients on pitches, I now look forward to utilising these skills at an agency like Addiction."
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This article was first published on campaignlive.co.uk