A wide increment of the object-oriented diffusion has been registered This is accompanied by the needs of metrics and tools for assessing class reusability, maintainability, complexity, etc. Metrics have to produce confident results and have to be continuously revalidated on the basis of specific purpose on their adoption. Tools for system assessment must be capable of satisfying the needs of each company by supporting the definition of more specific metrics and by providing appropriate views of software characteristics. These views are useful to give at the developers as well as at the managers immediately understandable representations of the system status. In this paper a new approach is proposed for system assessment. This approach is based on the adoption of new and well-known metrics together with a set of histograms and profiles that give a clear characterization of the system under development. The semantics of these histograms has been validated against several projects. A brief overview of the tool, TAC++, developed for system assessment has been also included.