Vaughton, nee Slatem, becomes global comms director (brands) as the hotel chain concludes a major comms and marketing review.
Vaughton will report to Yasmin Diamond, who joined IHG in January after leaving her role as comms director at the Home Office.
Starting in December, she will work alongside global comms director (corporate) Kari Kerr.
Vaughton joins after three years at MHP, where she was deputy head of brand.
She joined the agency in 2009 after working at Frank, Red Consultancy and Clarion Communications.
Gavin Devine, Chief Executive of MHP Communications said:
'Jo has made a fantastic contribution to MHP Communications over the past three years and we wish her all the very best in her new role.'
Vaughton said: 'The past three years at MHP working on big brand campaigns for multi-nationals, such as American Express, Disney and Coca-Cola, has been incredibly enjoyable and stands me in great stead for my next challenge at IHG. I'm looking forward to returning to a global role, combining my passions for brand building and travel.'