SAS will be responsible for developing Dunnhumby's access and management for its customer database, by automating the entire process and increasing the accuracy of its records.
Dunnhumby already uses SAS software to help manage its Tesco loyalty card scheme business.
The date firm said it had chosen SAS for its "ability to manage and store the sheer volumes of Dunnhumby customer data", and estimate that it will be able to halve the time it takes to return data on projects.
SAS will be specifically working on Dunnhumby's overseas retail, retail banking and mobile communications accounts for the firm.
Dave Annis, data solutions director at Dunnhumby, said: "We explore a client's data assets, identifying gaps and suggest new business opportunities derived from the data.
"With SAS we can deliver a faster and more efficient service -- this is our business, and we can't afford not to do it well."
Giles Pavey, group insight manager at Dunnhumby, said: "SAS has always been the analytical heart of Dunnhumby. If we can work out what we want to do, we just trust we can do it in SAS. That puts us in such a powerful position."
Dunnhumby recruited David Annis to head the company's 60-strong UK Data Solutions Group in August.
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