1. A system for an enterprise having multiple business units to communicate with a user over multiple channels, the system comprising: channel interfaces respectively coupled to the multiple channels; a knowledge management system coupled to the channel interfaces, the knowledge management system comprising: an offer database, the offer database storing potential offers to the user, the potential offers being supplied from the multiple business units; a user profile database, the user profile database storing a user profile with respect to the user; and a decision engine coupled to the offer database and the user profile database, the decision engine making a decision as to which of the potential offers to present to the user and which of the multiple channels over which to make the presentation.