Tim Castree, MEC's global chief executive, has been chosen to lead Group M's newly merged MEC and Maxus teams. The new agency is currently unnamed.
Alex Mahon, the chief executive of Foundry, has been named Channel 4's first female chief executive. She will replace David Abraham when she takes up the role in the autumn.
Andrew Benett has joined Bloomberg Media in the newly-created role of global chief commercial officer, reporting to chief executive Justin Smith, in New York.
Chris Williams starts his new role as chief executive of Publicis Media Exchange UK later this month. He will be responsible for a trading and investment portfolio that exceeds £1bn of billings a year, and report to Amanda Morrissey, Publicis Media's UK chief executive.
Luc Wise is joining Publicis as chief strategic transformation officer, reporting to Valérie Henaff, the chief executive of Publicis Conseil and global president of Publicis Worldwide.
Shadi Halliwell, Harvey Nichols' group marketing and creative director, is leaving the company and joining Three as chief marketing officer. Before joining the retailer in April 2014, she spent 23 years at O2 and its predecessor BT Cellnet in a series of roles including head of brand.
Nigel Roberts has joined Krow as creative director, reporting to executive creative director and founder Nick Hastings. His portfolio of clients will include Fiat, Ferrero and RNLI.
Shortlist Media has announced the appointments of Emily Palmer as head of digital, and Nicola Marsh as head of creative strategy. Palmer begins her role in mid-June, reporting into Owen Wyatt. Marsh began on 5 June and reports into Jo Sutherland and Ash Qureshi, heads of family.
Nicolas Verneuil has been appointed marketing director for Nissan Motor (GB), responsible for all marketing strategy for the UK.
Geraldine Ingham, Nissan's marketing director in France, has been named Volkswagen's head of marketing UK, replacing Rod McLeod.
Stink Studios has promoted James Britton to global managing director. Chief executive Mark Pytlik has resigned his post but will remain a company shareholder and advisor to the board.
Laura Izzard has been appointed marketing director of shopper and retail creative agency Haygarth. She joined the agency two years ago.
Eli Pinto, previously commercial director at Amaze, has been appointed chief executive of Sharp Co-Lab, a digital agency based in Shoreditch, London. Pinto began the role on 2 May.
Celebrity Cruises has appointed Sam Otter to the role of director of marketing and PR, UK and Ireland. She will report to Jo Rzymowska Celebrity Cruises' UK, Ireland and Asia vice president and managing director. Otter replaces Toby Shaw, who moves to the British Horse Racing Association.
Digital agency Burnthebook has made two new hires. David Hancock joins the design team as a graphic designer, and Rachel Redsell has been appointed to the role of project manager. They will both report to director Phil Newson.