Following a review of its financial PR, Serco invited seven agencies to pitch for the work, including Brunswick.
Marcus De Ville, group head of media relations at Serco Group, said: "Brunswick has provided Serco with a valuable service as our external financial PR adviser over the past nine years. In line with normal best practice, we have recently undertaken a thorough competitive process to review the support that we receive in this area. Following this review we have selected Maitland to be our financial PR adviser going forward."
Neil Bennett, Maitland chief executive, said: "We are really looking forward to working with Marcus and his team."
Serco has recently posted a revenue and profit fall, with sales at the company dropping to £1.8bn in the six months to 30 June, from £2bn in the same period last year. It has also lost its franchise to run the Docklands Light Railway in London, as well as a contract with the National Physical Laboratory.
Brunswick has recently won new clients including Johnson & Johnson, Dubai International Capital and Estee Lauder.
