Under the terms of the deal, all of STW’s field marketing, mystery shopping and customer auditing activities across Australia and New Zealand will be carried out in partnership with Smollan.

Field marketing specialist Smollan, which is part-owned by WPP, is headquartered in South Africa and has office in the UK, China, India and Malaysia.

Its chairman Doug Smollan said: “We feel a very strong cultural fit with STW, and see Australia and New Zealand as markets with big growth opportunities. Our experience and intellectual capital in people and technology solutions, combined with STW’s local relationships, provide enormous leverage. We’re looking forward to being part of that.”