This volume contains a selection of papers presented at thesecond European workshop EUROCAST '91, held in Krems,Austria, in April 1991. It gives an overview of the currentstate of Computer Aided Systems Theory research and itsrelation to CAD applications in the engineering fields. CAST research requires the application of the most advancedinformation processing technology in software and hardwarefor the implementation of CAST method base systems. Engineers in the field of information and controlengineering have the opportunity in CAST to present thestate ofthe art in modeling tools to computer scientists. EUROCAST '91 proved that CAST research is still in an earlystate of development. The papers in the volume are organized into sections onsystems theory and CAST methodology, modeling environments,CAST method base systems and artificial vision, andinformation and control systems.