Martin, who specialises in financial and professional services, has worked with clients including Bank of America, KeyBank and Hunton & Williams. Her new role is senior account director.
Tangerine has also promoted Helena Reid, who joined last year, to associate director. Reid will be part of the senior management team and will work across European business technology, manufacturing and facilities accounts as well as heading up the agency's marketing division.
Reid said: "Tangerine is one of the fastest-growing independent agencies in the UK, so joining the senior team to help build and drive that success is something I’m really excited about. With such a great team in place I can’t wait to be part of the next phase in Tangerine’s development."
Elsewhere in the consumer sector, the agency has hired Tom Gibson from Motocom as an account executive and Harriett Geoghegan as a junior account executive from beauty brand Crème De La Mer.
Tangerine's clients include Peugeot, Dulux and E.ON.