An apparatus (22,44) is described for use in generating configuration information for a computer system (12) employing hierarchical entities. A policy template (24) is employed which contains a definition of an abstract high-level policy, for the configuration of the system, and permitted refinements to that policy, the definition referring to a plurality of the entities. An information and system model (16) contains information about the computer system and its environment including the entities referred to in the high-level policy definition, the hierarchy thereof and non-hierarchical relations between the entities. A policy authoring engine (26) refines the high-level policy definition with reference to the permitted refinements thereto and the stored information about the entities to which the high-level policy definition relates in order to produce a refined policy definition. In doing this, the engine presents refinement options to a user (10) via a user interface (28) and refines the high-level policy definition in dependence upon options selected by the user via the user interface. Some of the entities stored in the model (16) may be abstract entities, but with pointers to data in the computer system representing an instance of that abstract entity. The refined policy may be in terms of a policy context, referring to unbound entities, and a policy statement. A policy deployer (20) stores rules for interpreting the policy statement as instructions executable by the computer system and is operable, with reference to the information and system model (16), to bind the unbound entities in the policy context to instances of those entities, and, with reference to the stored rules, to interpret the policy statement into a series of instructions to the computer system referring to the bound instances or derivatives of them. The apparatus facilitates the refinement of abstract policies and implementation of the refined policies.