Everitt replaces Nick Blunden, who was promoted to chief executive earlier this year following the departure of the European chief executive, Daniele Fiandaca.
In his new role, Everitt will be responsible for building stronger relationships with the agency's existing clients in a bid to help it evolve from digital specialist to lead communications agency.
During his time at Sapient, Everitt was the global account director on Unilever. Before that, he was the group account director at AKQA, where he worked on the agency's Dell business.
Everitt's appointment caps a year of change for Profero's senior management team. In July last year, the agency recruited the Zig founder, Elspeth Lynn, as its new executive creative director, and appointed VCCP's Dale Gall to the newly created role of global planning officer.