Shilling (pictured) takes the role of EMEA executive vice president, growth.
Porter Novelli said she will be responsible for evolving the agency offering in EMEA and "adding firepower to its regional marketing and new business efforts". She will "lead the strategic building of the brand, its offering and EMEA client portfolio", the agency added.
Shilling will report to Fenella Grey, who was promoted to MD for the EMEA region in March.
Before joining Unlimited Group, Shilling was head of corporate communications at Pernod Ricard UK and global head of brand communications for Intercontinental Hotels Group.
Shilling, who is set to join Porter Novelli in mid-May, is a judge at the Brand Film Awards this year, is on the advisory board for female investor network Angel Academe, and is an ambassador for NABs – the support organisation for the UK advertising and media industry.
Grey said: “We are ready to bring our proposition into the marketplace. We have been quietly brilliant. It's time to make some waves and tell the world how progressive we are in helping our clients build resilient reputations. Sarah brings high energy, a winning blend of senior leadership skills and wide understanding of marketing to accelerate growth out of our EMEA hub In London."
Shilling said: “What the Porter Novelli leadership team has built is impressive; they have the talent, the momentum, and most importantly, an unwavering commitment to align clients' intentions with actions – it’s such a compelling offer. The trajectory for growth is phenomenally exciting and I can’t wait to work with the team to add firepower to the ambition.”
Her appointment follows a period of senior leadership changes, in the UK and globally, at the Omnicom network agency last year.
Global CEO Brad MacAfee left the agency in 2019 - his replacement, David Bentley, joined in March 2020.