As part of the senior management restructure, Neil Ireland, a former Bartle Bogle Hegarty planner, has been hired as the planning director.
Ireland had previously been running his own consultancy in London.
The trio will report to the head of the Edinburgh office, Gary O'Donnell, who was previously a partner in the London agency.
"This expansion, at a time when the industry in Scotland has been contracting, is a measure of our commitment to the Scottish market," the TBWA\ London chief executive, Andrew McGuinness, said. "Agencies often preach the benefits to clients of investment during downturns. The same logic applies to agencies. After some difficult times across the industry, we feel that opportunities are starting to open up."
TBWA\Edinburgh, which has been running for a year, was responsible for Scottish Labour's successful re-election campaign in May 2003.
Mawhinney and Bastiman assumed creative control of Faulds in August last year when the incumbent creative director, Billy Mawhinney, returned to J. Walter Thompson for the fourth time in his career. The pair, who had been the joint deputy creative directors, ran the creative department until Faulds went into liquidation in late September, having lost several major clients.