In the design, implementation, and operational planning of computer and c- municationsystems, manyquestionsregardingthe desiredcapacityandspeed of (sub)systems have to be answered.At this point, performance anddependability evaluation techniques can be of great help. With these techniques, design de- sions can be prepared using advanced methods to construct appropriatemodels, toparameterisethesemodels, andtosolvethem.Theapplicationofabroadsp- trum of such methods and techniques is currently supported by tools (mostly software, but sometimes partly hardware as well). Such tools enable system - signers and engineers to construct their models in a ?exible and modular way using high-level application-oriented modelling languages, to solve their models with a variety of techniques and to exercise parametric studies at ease. The goal of the 11th International Conference on Modelling Tools and Techniques for Computer and Communication System Perf- mance Evaluation (\TOOLS 2000") was to further develop the theory and technologyfortool-basedperformanceanddependability evaluationofcomputer and communication systems. Important themes included software tools, eval- tion techniques, measurement-based tools and techniques, performance and - pendabilityevaluationtechniquesbasedonformalmethods, casestudiesshowing the role of evaluation in the design of systems, and application studies in the area of centralised and distributed computer systems. Previous conferences in this series were held over the past 15 years in Paris (1984), Sophia Antipolis (1985), Paris(1987), Palma de Mallorca (1988), Torino (1991), Edinburgh (1992), Wien (1994), Heidelberg (1995), Saint Malo (1997), and Palma de Mallorca (1998). The proceedings of the latter four conferences also appeared in the series Lecture Notes in Computer Science (Volumes 794, 977, 1245, and 1469, respectively).