His appointment follows the departure of Daniele Fiandaca, Profero's European chief executive, who left the agency last month.
Blunden will now be responsible for overseeing the day-to-day operations of all of Profero's businesses, which incorporates ad agency Profero London, technology agency Profero Connect, media business Profero Performance, and social media outlet Yabber.
He has worked at Profero for just over five years, joining the agency in October 2004 as client services director.
He was promoted to the role of managing director in April 2007, following an internal restructure of the agency's senior management team.
In his role as managing director, Blunden was responsible for making a number of key hirings, including the appointment of Elspeth Lynn as executive creative director from the Canadian agency Zig.
Before joining Profero, Blunden spent time as a project manager for telecommunications company Energis and as a management consultant for IBM Consulting.