Most of the articles in this volume are revised versions of papers presented during the 1st GROOM-Workshop on the Unified Modeling Language (UML). GROOM (Grundlagen objektorientierter Modellierung) is a working group of the Gesellschaft fur Informatik (GI), the German Society of Computer Science. The workshop took place at the University of Mannheim (Germany) in October 1997; the local organizers were Martin Schader and Axel Korthaus, Department of Information Systems. The scientific program of the workshop included 21 talks, presented in German language on Friday, Oct. 10th, and Saturday, Oct. 11th, 1997. Researchers and practitioners interested in object-oriented software development, analysis and design of software systems, standardization efforts in the field of object technology, and particularly in the main topic of the workshop: ''Applications, State of the Art, and Evaluation of the Unified Modeling Language" had the opportunity to discuss recent developments and to establish cooperation in these fields. The workshop owed much to its sponsors and supporters - University of Mannheim - Faculty of Business Administration, University of Mannheim - Sun Microsystems GmbH - Apcon Professional Concepts GmbH. Their generous support is gratefully acknowledged. In the present proceedings volume, papers are presented in three chapters as follows.