Proceedings of the 3 rd International Modelica Conference, Linköping, November 3-4, 2003, Peter Fritzson (editor) Paper presented at the 3 rd International Modelica Conference, November 3-4, 2003, Linköpings Universitet, Linköping, Sweden, organized by The Modelica Association and Institutionen för datavetenskap, Linköpings universitet All papers of this conference can be downloaded from http://www.Modelica.org/Conference2003/papers.shtml Program Committee  Peter Fritzson, PELAB, Department of Computer and Information Science, Linköping University, Sweden (Chairman of the committee).  Bernhard Bachmann, Fachhochschule Bielefeld, Bielefeld, Germany.  Hilding Elmqvist, Dynasim AB, Sweden.  Martin Otter, Institute of Robotics and Mechatronics at DLR Research Center, Oberpfaffenhofen, Germany.  Michael Tiller, Ford Motor Company, Dearborn, USA.  Hubertus Tummescheit, UTRC, Hartford, USA, and PELAB, Department of Computer and Information Science, Linköping University, Sweden. Local Organization: Vadim Engelson (Chairman of local organization), Bodil Mattsson-Kihlström, Peter Fritzson. Michael Tiller, Paul Bowles, Mike Dempsey Ford Motor Company, USA; Claytex, UK: Development of a Vehicle Modeling Architecture in Modelica pp. 75-86