Hardbound. The book describes current research and development activities carried on by the DATAID research project in the area of methodology and tools for database design. The present book is divided into two parts. The first part is devoted to the description of tools that have been developed in order to support the conceptual, logical and physical design of a database application. The second part is devoted to a review of the DATAID-1 manual methodology, together with reports of its experimentations and with proposals of extensions as regards distributed design and dynamics handling. Main Features of this book are: 1. Indications of the basic characteristics for a tool which supports the design activities and handles the related documentation. 2. Considerations about the role of tools with respect to methodologies. 3. Description of several advanced tools developed for the various design phases. 4. Considerations about the role of methodologies in t