Glen Calvert, founder of programmatic marketing company Affectv, is stepping down from his role as chief executive.

Taking the reins will be Patrick Johnson, who currently serves as chairman of the seven-year-old firm. Before joining Affectv, Johnson held top roles at Leo Burnett, TBA Global and WPP.

In a Medium post, Calvert said his seven years at the helm have been an “incredible journey,“ one that involved growing the business from “a tiny office in Soho” to a global operation with offices across the US and APAC.

“Startups are exhilarating, terrifying, and rewarding beyond description. But deciding the right time to move on from a business you founded can be the hardest decision of all. It’s a decision that can only be made when you have a management team with depth of experience and exceptional skills,” Calvert wrote.

“Patrick brings this to the role having scaled advertising businesses, and in particular having held executive positions at Publicis and WPP. Combined with the support from our outstanding team, Affectv is well placed to achieve our mission.”