Learning Classifier Systems (LCS) are a machine learning paradigm introduced by John Holland in 1976. They are rule-based systems in which learning is viewed as a process of ongoing adaptation to a partially unknown environment through genetic algorithms and temporal difference learning.

Basics.- What Is a Learning Classifier System?.- A Roadmap to the Last Decade of Learning Classifier System Research (From 1989 to 1999).- State of XCS Classifier System Research.- An Introduction to Learning Fuzzy Classifier Systems.- Advanced Topics.- Fuzzy and Crisp Representations of Real-Valued Input for Learning Classifier Systems.- Do We Really Need to Estimate Rule Utilities in Classifier Systems?.- Strength or Accuracy? Fitness Calculation in Learning Classifier Systems.- Non-homogeneous Classifier Systems in a Macro-evolution Process.- An Introduction to Anticipatory Classifier Systems.- A Corporate XCS.- Get Real! XCS with Continuous-Valued Inputs.- Applications.- XCS and the Monk’s Problems.- Learning Classifier Systems Applied to Knowledge Discovery in Clinical Research Databases.- An Adaptive Agent Based Economic Model.- The Fighter Aircraft LCS: A Case of Different LCS Goals and Techniques.- Latent Learning and Action Planning in Robots with Anticipatory Classifier Systems.- The Bibliography.- A Learning Classifier Systems Bibliography.