The agency, which replaces PR21 on the account, is now tasked with boosting sales in the UK and Europe though media relations, product placement and sponsorship. It also acts as Speedo's press office.
The Sputnik team, headed by partner Penny Furniss, reports to Paul Phedon, associate director of marketing.
Account director Lucy Hackett said: 'We have been hired to revitalise the brand. This will include more of an emphasis on the products in terms of the beach and leisure. But the Olympics and Speedo's association with that are still key to promoting the brand.'