Applications requiring sophisticated modeling techniques raise challenging issues to software designers. CAD/CAM and genetics are example of applications that call for powerful modeling techniques. Existing approaches seem limited in their ability to supports their demands. Relational database systems for example support only simple tables. The need to enhance their capabilities led to non-normalized relational data models. Object-oriented programming languages and databases propose new solutions to the problem of complex and composite object modeling and manipulation. Yet, severe shortcomings impede their practicability, e.g., their inability to model multiple object representations and complex semantic relationships. This paper is an informal overview of a data model called SHOOD implements sophisticated features, such as : o object persistence, multi-methods along a specific specialization hierarchy (which is independent of the class hierarchy), o sophisticated semantic relationships, e.g., dependency relationships between objects (which are totally independent of the composition relationship), o multiple object representations, allowing the users to manipulate the objects from several points of views simultaneously, o the systematic use of a powerful meta-object kernel, which is used to implement a reflexive architecture. The paper focuses on the last two issues.