Hainsworth is joining the UK management team of Media Audits as a partner, working alongside the recently recruited Tony Emment and Nick Sparey.
Her departure is a blow to Mediahead, formerly CDP Media, which has suffered a series of account losses since it rebranded in May 2002. Last September, the WPP and Dentsu joint-venture agency lost its £24 million Honda account to Starcom Motive. Honda was the biggest single account at Mediahead.
Hainsworth was made the managing director last October following the departure of Peter Thomson. Thomson re-emerged with a role at Manning Gottlieb OMD.
"The opportunity at Media Audits is a very exciting new stage in my career. It has a very strong network across Europe and is expanding globally. I understand the issues facing media agencies today and I want to address them directly. Most importantly, Media Audits is committed to helping promote trust and accountability in the client agency relationship, as am I," Hainsworth said.
Media Audits has handled recent media reviews including Revlon, Wrigley and Axa insurance.