InhaltsangabeI Introducing Qualitative Reasoning.- 1. Instead of a Definition.- 2. Tasks of Qualitative Reasoning.- 3. Basic Principles.- 4. A Short History.- II The Basics of Qualitative Reasoning.- 1. The Main Approaches.- 1.1 The Device-centered Ontology.- 1.2 The Process-centered Ontology.- 1.3 The Constraint-based Ontology.- 2. Correspondences and Differences.- 3. Dimensions of Qualitative Mapping.- 4. The Reasoning Techniques of the Main Approaches.- 4.1 The Constraint-based Ontology.- 4.2 The Device-centered Ontology.- 4.3 The Process-centered Ontology.- III Advanced Topics.- 1. Some Remarks on Causality.- 2. The Problem of Ambiguity - Improvements in the Representation of Structure and the Generation of behavior.- 3. The Representation of Uncertainty.- 3.1 Fuzzy Sets Used in Qualitative Reasoning.- 3.2 QUALSIM.- 3.3 A Representation Based on Markov Chains.- 4. A Graph-based Interpretation of Qualitative Models.- IV Qualitative Reasoning and Related Fields.- 1. Simulation in System Theory.- 2. Qualitative Reasoning and Expert Systems.- 3. Modeling Human Reasoning - a Short Look at Cognitive Science.- V Modeling in Qualitative Reasoning.- VI Conclusion and Suggestions for Further Research.- References.