Gyro willl be responsible for managing and developing a CRM database, which will also cover other Moss Bros brands such as Moss, Moss Bros Hire and Beale & Inman.
Gyro was originally appointed by Moss Bros to launch the company's sale, new season communications and mail order catalogue.
Andrew Barclay, head of marketing at Moss Bros, said: "Having managed other areas of our business and successfully launching our mail order catalogue, we were confident they would be the best agency to handle this area."
Richard Perry, managing director of Gyro International UK, said: "Gyro has a significant expertise built over the last 14 years working with business-to-business clients in segmenting data and building profile models. This expertise can be transferred to the retail market and will enable Moss Bros to monetise its existing database."
The appointment follows Gyro's aggressive growth strategy that has seen it recently open an office in Hamburg and look to develop its business in France and Spain.
The firm has also seen its Sun Microsystems account grow and has won direct marketing work with Sony Electronics and SportsAid.
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