Preface. Intelligent Agents. General Presentation of the Disciple Approach for Building Intelligent Agents. Knowledge Representation and Reasoning. Knowledge Acquisition and Learning. The Disciple Shell and Methodology. Case Study: Assessment Agent for Higher-Order Thinking Skills in History. Case Study: The Statistical Analysis Assessment and Support Agent. Case Study: Design Assistant for Configuring Computer Systems. Case Study: Virtual Agent for Distributed Interactive Simulations. Selected Bibliography of Machine Learning, Knowledge Acquisition, and Intelligent Agents Research. Notation. Subject Index.