Methods, models, apparatus and systems for determining impact of a change in a specification on one or more services to be used by an enterprise are presented. For example, a method for determining impact of a change in a specification on one or more services associated with an enterprise includes obtaining the change in the specification associated with the enterprise, obtaining enterprise elements, obtaining structural rules stating relationships among the enterprise elements, obtaining one or more pre-defined impact rules indicating one or more possible changes associated with the enterprise, and determining the impact of the change in the specification on the enterprise. The one or more pre-defined impact rules have been pre-defined independent of the one or more services to be used by the enterprise. The impact is determined according to the change in the specification, the enterprise elements, the structural rules and the one or more pre-defined impact rules. One or more of obtaining the change in the specification, obtaining the enterprise elements, obtaining the structural rules, obtaining the one or more pre-defined impact rules, and determining the impact are implemented as instruction code executed on a processor device.