The past few decades have witnessed remarkable growth in the application of passive seismic monitoring to address a range of problems in geoscience and engineering, from large-scale tectonic studies to environmental investigations. Passive seismic methods are increasingly being used for surveillance of massive, multi-stage hydraulic fracturing and development of enhanced geothermal systems. The theoretical framework and techniques used in this emerging area draw on various established fields, such as earthquake seismology, exploration geophysics and rock mechanics. Based on university and industry courses developed by the author, this book reviews all the relevant research and technology to provide an introduction to the principles and applications of passive seismic monitoring. It integrates up-to-date case studies and interactive online exercises, making it a comprehensive and accessible resource for advanced students and researchers in geophysics and engineering, as well as industry practitioners.