The acquisitions boost the size of WSP by more than 500 employees, taking its worldwide workforce past 8,000.
Sells is a transport and infrastructure engineer with particular expertise in bridge design and engineering. CBP Consulting Engineers is a leading German engineering and project management group.
WSP chief executive Chris Cole said: “Both Sells and CBP are regarded as leaders in their respective fields and I am delighted we have secured the services of the entire management teams of both companies who are committed to the vision and values of the WSP Group.”
Sells operates from eight offices across eastern USA and is currently working on a number of major transport projects in New York City including the £250M interim reconstruction of the four-mile long Gowanus Expressway Viaduct and the £125M replacement of the approach structures to the Bronx Bridge.
CBP is based in Munich and current projects include work on Berlin International Airport; the planning co-ordination of terminal extensions at Frankfurt Airport; project management of the convention and conference centre at the Mercator Hall in the Duisburg City Palais and multi-disciplinary services for a 39,000 square metre mixed use development in the centre of Munich.