An enterprise system consists of a number of components or building blocks. It is common to use views or models of the enterprise that contain a selection of these components (dependent on the intended usage of the model). The premise is that if these views are considered systems in their own right then the total enterprise system is actually a system-of-systems. Difficulty arises however when the boundaries between the systems overlap - it is therefore necessary to have an integrated model of the total enterprise that can cope with these overlaps and hence interactions between the systems. Within this paper there will be two main areas of work described; firstly the development of models/tools of "soft" enterprise characteristics; and secondly how these characteristics may be included in an integrated model of an enterprise system. Case studies of UK organisations (primarily within the defence industry) were undertaken to provide context to the results. © 2007 by G.A.L. Kennedy.