A method and system for associating search keywords with interest spaces. According to one embodiment, a method may include detecting a request to access a given online content source, where the request includes referral information specifying one or more search keywords associated with the given online content source, where the given online content source is one of a plurality of online content sources included within an interest space, and where the interest space is identified dependent upon indications of user navigation activity among the plurality of online content sources. The method may further include extracting the one or more search keywords from the request and creating an association of the one or more search keywords with the interest space.