Luiz Pastor, FSB customer care director, will head a team of two staff in charge of the account, reporting to Christiane Franck, Continental's country director for Brazil, and Sandra Kaspar, its local marketing manager.
Hill and Knowlton held the account previously, according to Pastor.
Continental is the second largest US airline in South America in terms of flight numbers and passengers. It entered Brazil five years ago, where it has two daily flights linking Sao Paulo to New York and Houston, and plans to add a further route to New Orleans.
FSB was founded 23 years ago, and currently has about 70 staff across officeds in Rio de Janeiro, Sao Paolo and Brasila.