Profero's remit involves strategy, creative and media buying and includes the use of direct mail and press advertising as well as online activity.
The hire follows a less formal relationship in which Profero carried out a series of projects for Overture, including a series of press advertisements last month targeting SMEs through the technology press.
Overture marketing manager Teresa Virani said: "We believe that Profero can help us tell the market place about our offering and acquire us more customers."
Last month Overture, which is based in Pasadena, California, appointed former chief executive of Securicor eSolutions Stephen Taylor as its managing director for Europe, replacing Nick Hynes.
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