Hollingsworth, who starts his new role on July 29, will be tasked with developing 's business and building on its current offering, to provide a more complete design and innovation service.
He joins from Parker Williams where he was managing creative director.
Hollingsworth started his career as a product designer with Interbrand and moved into Craton Lodge and Knight and then to Michael Peters and Coley Porter Bell. He also worked as managing director at Brown Inc and Enterprise IG.
He said: "This is a really exciting move for me. Vibrandt is a strong brand and the 1HQ team are passionate about seriously growing the business.
"We have got all the disciplines working together under one roof to deliver compelling design solutions based on fantastic consumer insight. Clients are crying out for speed to market and they need a company like Vibrandt to deliver just that."
Clients of 1HQ include Unilever, Nestle Purina, Premier Foods, Coca Cola, Sony BMG, Pernod Ricard, and AOL.
John Sandom, chief executive of 1HQ, said: "I have known and respected Pete for a long time. He has always been a formidable adversary; I'm very much looking forward to having him on our side.
"His intuitive creativity and blue-chip experience makes him the ideal leader of Vibrandt."