This paper describes a Development Environment for medical applications developers coupling Reuse and Object-Oriented technologies. It presents the two main phases of the reuse process, the reusable component creation and the reusable component use, and stresses on the very nature of reusable development components. We provide both a classification model for those reusable components that is a support for an efficient and simple retrieval mechanism, and a reusable component model that considers the same way components of large and low-granularity levels (e.g., application frameworks and methods of a given class). The reusable component model is based on the underlying idea that development components are not operational components since they do not have the same purpose. This model first represents each component as an aggregation of other sub-components, together with all information needed for its retrieval (e.g., classification and facets), its understanding (e.g., informal functional description), and its dependencies with other development components, in particular the applications in which it occurs, since applications are considered here as abstract development components.