Her role will be split between sister company Weber Shandwick's deputy consumer head Matt Neale and WS tech practice director Jonathan Hughes.
Arden has led Golin Harris in the UK for the past two years and will hand over to the WS duo from 1 October. She plans to take a six-month break to spend time with her family before considering a move in-house.
Neale takes over the joint running of the technology, consumer and corporate agency after eight years at WS. Hughes joined WS in 2001 from Ketchum.
The pair will report to US-based Golin Harris chief executive Fred Cook and WS UK & Ireland chief executive Colin Byrne. WS is seeking their replacements.
Byrne said: 'The Golin Harris brand was important when we transferred Zoe across and it is even more so now. WS is a big agency and can overwhelm clients who want something smaller.'
Neale and Hughes approached Byrne to propose splitting the role. 'We think we can grow this business with the skills we have between us,' said Neale.
Arden was MD of technology agency Weber Group before its merger with Golin Harris International in May 2003. Clients now include National Express and software giant Oracle.
Prior to Golin Harris, Arden ran the B2B practice group for San Francisco-based agency Access Communications.
- Health information provider Doctor Foster has hired Golin Harris to raise its profile and support product launches such as further information guides.
The company promises to be an increasingly important resource for patients from 2006 when they will be able to choose between four or five hospitals when referred for surgery by their GP.
Doctor Foster previously co-produced supplement The Sunday Times Good Hospital Guide.