1. A method for managing a set of computing resources, the method comprising: importing descriptions of computing resources from a plurality of heterogeneous sources, wherein the descriptions specify categories for the computing resources, wherein different sources use different types of categories for the resource descriptions; and based on the categories specified for the computing resources in the set, deriving additional categories for at least a subset of the computing resources; storing each imported computing resource tagged according to its specified and derived categories, wherein the category tags are used for binding policies to the computing resources.