Kirsty Leighton has been appointed managing director for the UK and Ireland, replacing Nick Giles.
She said: ‘From my perspective I'm keen to reinvigorate the brand. Text 100 is an international network but in the UK it seems to have moved into the background.'
Leighton takes up her new role on 19 April and will report initially to Text 100 global chief operating officer Andrew McGregor. Giles quit Text 100 in November to set up Seven Hills with Communications Group chief executive Michael Hayman.
Leighton added that she plans to move the agency from being perceived purely as a tech offering to consumer.
McGregor said: ‘We've intentionally sought a leader with broad global credentials and a proven ability to diversify the mandate of a technology-centric agency.'
McGregor added that he has challenged the new senior team to ‘double the size of our UK business within two years'.
The appointment is the latest in a line of high profile appointments at the agency, including director for Text 100's enterprise IT business unit Jonathan Brayshaw and Dan Baxter, who has been promoted to deputy managing director.
Leighton has more than 16 years of public relations experience, having worked at Edelman Public Relations Worldwide and the former Weber Group Europe.
Waggener Edstrom is currently using existing people on the business to cover McGregor's work, but a new appointment will be made.