Three UK has appointed ex-Telefónica marketer Katrina Ward-Smith to director of brand and marketing communication.
Ward-Smith has been filling the role on an interim basis since earlier this year.
Reporting to chief marketing officer Shadi Halliwell, Ward-Smith will be responsible for the strategic direction of the Three brand in the UK.
She spent more than a decade in numerous roles at Telefónica, latterly as head of creative, media and content for O2.
Before joining the telecoms sector, Ward-Smith served as an account director at Grey London in New Zealand.
Halliwell said: "Her experience will be a vital asset to our business as we continue to work towards becoming a truly customer-centric brand."
Ward-Smith added: "Having worked in the industry for many years, I’ve long admired Three’s disruptive approach as a challenger brand. I am thrilled to be joining such a bold, creative team.
"I am looking forward to working with the talented team we have in place and to push the boundaries to move the business forwards in new and exciting ways."
Last month, Three launched the "Phones are good" campaign, by Wieden & Kennedy London, showing how smartphones may have improved life in the past.
The spot was selected as Campaign’s Pick of the Week, with Simon Gwynn suggesting that the film benefits from "sharp writing, nice production values and very enjoyable performances".