Systems and methods for providing a searchable concept network are provided. One such system includes a concept network application, which is hosted at least partially on a server. The concept network application may include or access an indexer for indexing text corpus. The text corpus is analyzed to extract concepts, as well as significance, relevancy and relationship information between concepts. The concepts and associated significance, relevancy and relationship information are utilized to construct a concept network, which is stored in one or more indexes or databases accessible to the concept network application. One or more user computer devices are provided access to the application, which receives a query from the user, and in response, provides the user with a relevant portion of the concept network. User behavior or interaction within the concept network may be detected and utilized in providing relevant advertisement information.