Bigg, who has been at Edelman for more than 15 years, succeeds former MHP chief executive Gavin Devine, who left to join Porta Communications as chief operating officer earlier this year. He is expected to start in mid-November.
PRWeek UK Power Book entrant Bigg has been general manager at Edelman UK, the country’s biggest PR agency by revenue, since 2013. His previously roles at the agency have included group MD, corporate and financial, and MD, public affairs.
Engine-owned MHP employs more than 175 people across its disciplines of corporate affairs, health, financial, brand and design. As well as the London HQ, Bigg will oversee MHP’s offices in Hong Kong, Sydney and Germany.
Debbie Klein, CEO of Engine Europe and Asia Pacific, said: "We are thrilled Alex is joining MHP. Alex has a very sure view of how to bring together all of MHP’s skills to capitalise on the major changes we are seeing in the industry. He is one of the most respected corporate counsellors in the UK and has a proven track record of successful agency leadership.
"MHP has made great strides this year with the quality of work the team have been producing and the recognition it has rightfully received from its industry peers. Alex will consolidate that success and provide new drive and vision. It is going to be an exciting time."
Bigg said: "I am absolutely delighted to be joining MHP. It is an agency whose fortunes I have followed over many years. I am looking forward to working with some of the smartest people in the industry to realise the agency’s full potential and to grow the business.
"I am also excited about working alongside the other specialist companies within the wider Engine Group, who are all leaders in their own field. It’s going to be a challenging but exciting process."
In a statement, Edelman said: "After more than fifteen years at Edelman, Alex Bigg has made the decision to take on a new challenge and will be leaving the firm. As general manager he has successfully lead our corporate and public affairs business for more than three years, been integral to the integration of the Smithfield acquisition and overseen our team in Ireland. He is a well-respected, committed leader and has contributed greatly to the growth of the firm. We wish Alex all the best in his next endeavour."
The agency added: "We are actively looking for a new general manager who has deep experience within the corporate, public affairs and financial space and is at the cutting edge of the innovations and integration taking place within the communications industry."