James Pillar, the British marque's director of marketing communications, said he was looking for a lead and strategic agency to take on a brief that will include all below-the-line and event-based marketing.
He added that work was under way to determine Bentley's future brand strategy, including its positioning and 'brand language'.
The changes will not affect Bentley's brand identity. However, it will involve overhauling the way that it is presented to customers, including its retail environment and digital communications. The brief is unlikely to include above-the-line advertising.
In 2006, Bentley posted sales of more than 10,000 cars, up from 8,627 in 2005.