1. A system for managing a knowledge model defining a plurality of entities, the system comprising: an extraction tool for extracting data items from disparate data sources; an integration tool for integrating the data item into the knowledge model; a relationship tool for identifying, automatically, a plurality of relationships between the plurality of entities; and a data visualization tool for presenting the plurality of entities and the plurality of relationships; where the extraction tool determines if the data item has been previously integrated into the knowledge model, and the integration tool integrates the data item into the knowledge model only if the data item has not been previously integrated into the knowledge model.