As concern over high energy costs mounts, the firm is looking to shore up its direct marketing activity as rival energy companies, including Powergen and British Gas, continue their bid to win more customers.
EDF Energy are hoping that CACI's data will help gain further insight into existing customers as well as identify new markets and better target campaign activity.
Robin Melvin, EDF Energy's head of data and customer insight, said: "This partnership will help us to focus our campaigns and meet demanding annual targets."
CACI is using its data classification systems Ocean and Acorn for the work.
Tracy Weir, CACI vice-president, said: "Working with EDF Energy is a major achievement and confirms our position as a forerunner in the database hosting sector."
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