The book "Learning Classifier Systems in Data Mining" offers a comprehensive analysis of the Learning Classifier System (LCS) paradigm, which has been in research and application for over thirty years. It highlights the ability of LCS to solve complex real-world problems, particularly in the field of data mining. The authors present a variety of applications and demonstrate the power of LCS across different domains. The first part of the book describes the main forms of LCS and provides a historical overview of their use in data mining. The subsequent sections address current research on LCS in key areas of machine learning and data mining, including classification, clustering, time series and numerical forecasting, feature selection, ensembles, and knowledge discovery.