Changes in the real world may require both the database population and the database schema to evolve. Particularly, this is the case in CAD/CAM and CASE database systems, in which the design objects constantly evolve in every aspect. On the other hand, the prototyping of a database design may also involve changes to both the structure and behavior of a schema. Unfortunately, most of the current systems offer little support for schema evolution. In this paper, we survey the recent development of the research in the schema evolution of objectoriented databases. The main issues in the current research are identified.