He will have increased management responsibility in his new position, overseeing Initiative’s broadcast trading relationships.
Temperley will report into Richard Oliver, the managing director of Magna Global, the strategic trading unit of IPG Mediabrands, the parent company of Initiative UK.
Temperley first joined Initiative in 2002 as director of TV and has served as head of TV since January 2012. Dave Walker who has been with Initiative UK for 14 years and is currently a senior activation director, replaces him.
Sally Weavers, the managing director of Initiative, said: "It's always great to be able to promote from within. James has been very loyal to Initiative and is both loved and respected by colleagues and clients."