The fascinating world of lichens and their specific applications also explores the many applications of lichens beyond dyeing. As indicators of pollution, lichens play a crucial role in environmental monitoring. Their industrial use in perfumery, cosmetology and pharmacology are discussed in this book, with particular emphasis on their use in dyeing. It also examines the problems associated with synthetic dyes and their impact on the environment and health, and advocates the use of environmentally-friendly alternatives. In addition, the book provides a comprehensive overview of the different types of lichen used for dyeing, focusing on their distinct chemical compositions and coloring properties. In addition, it presents the results of recent research in Tunisia on the distribution, diversity and metabolites of local lichens, offering a captivating dive into the world of lichens and their dyeing applications. In short, this book serves as a comprehensive guide for those seeking to discover the world of dyeing lichens.