Dawson said the agency will aim to work on global campaigns for brands that "don’t shy away" from big ideas.
His partner in the venture is Clive Pickering, the former head of copy at BETC London. Pickering left the agency at the same time as Dawson and the chief executive, Matthew Charlton. Charlton will join Brothers and Sisters as its chief executive at the end of April.
Dawson and Pickering are speaking with potential investors in the start-up and currently working with freelancers.
At BETC London, the pair worked on Bacardi’s global advertising account and the EMEA Diet Coke business.
Dawson said: "We have a history of working on big accounts so, even though we’ll be starting small, when you get down to it, it’s like on Bacardi: you don’t have to have that many people to create a global campaign."
Dawson said of his time at BETC London, which ended in tensions with his co-founder Charlton: "It’s difficult to talk about it because it didn’t end very well, but we [Pickering and I] both came out of BETC having loved the first two years. Now, it’s about taking all that learning and doing it again without the things that didn’t work so well."
Dawson Pickering’s debut work, the first above-the-line campaign for the store package delivery company CollectPlus, launched this week. The account was awarded without a pitch.