Edward Walsh will succeed Murphy to the role of MD of the firm's London office.
‘Both Darren and Edward have the experience and skills needed to drive our business forward in new and important directions,' said APCO Worldwide EMEA CEO Brad Staples.
Walsh is charged with growing the London office and building its corporate communications services for clients. Prior to his work at APCO, he spent nine years in senior corporate communication positions at IBM, where he managed internal and executive communication in EMEA. He also served as director of corporate communications for IBM France Northwest Africa.
Murphy will assume a new global position, with overall responsibility for APCO's services to governments work and overseeing business development.
Prior to joining APCO, Murphy served as special adviser for political communications to former Prime Minister Tony Blair. More recently, he was head of government relations and external affairs for AstraZeneca UK.