She takes up the new role on 1 October, and will be responsible for setting the digital vision, products and service requirements for Connected Execution, created in 2015 to focus on paid search, paid social and programmatic buying. It is expected to have 165 employees by the end of the year.
Long will work alongside Syma Nassar, director of operations for Connected Execution and Worldwide Hubs, who will continue to lead day-to-day operations for the division, which specialises in performance marketing and ecommerce.
She arrives at MediaCom after a short stint at the helm of iProspect, having joined from fellow Dentsu Aegis Network agency Carat as a replacement for Havas Media-bound Matt Adams. She, in turn, was replaced as iProspect managing director by Jack Swayne in December 2017. He reports to UK chief executive Stefan Bardega.
Kate Rowlinson, managing director of MediaCom’s World Wide Hubs business, said: "We’re thrilled that Felicity will be joining the MediaCom Connected Execution team.
"Her digital product, client and team leadership capabilities will ensure that we continue to provide unbeatable and marketing-leading insights into the platforms that all brands need to master. She is a proven driver of agency success and I know she’ll be a huge asset to our business."
Long added: "I’m very excited to be joining MediaCom, which has been an agency that I’ve admired as a competitor and media practitioner for years. The team in Connected Execution is hugely passionate about delivering great work that is admired across the industry. I’m looking forward to playing my part in working with the leadership team to continue to build on that success."