This volume reviews our current knowledge and novel research areas on Pochonia chlamydosporia, a cosmopolitan fungus occurring in soils as a saprophyte yet capable of colonizing the rhizosphere of crops as an endophyte and behaving as a parasite of eggs of plant-parasitic nematodes. The book is divided into six sections containing 18 chapters, starting with a historical background chapter, followed by 16 chapters, each contributed by experts, concerning those key aspects necessary to work with this biocontrol agent in a multidisciplinary treatise. Topics covered include systematics, biology, nematode-fungus interactions, nematode management strategies, secondary metabolites, and other methods including more novel research areas such as molecular, –omics, plant growth enhancement and endophytic abilities of P. chlamydosporia. The final chapter deals with the future perspectives of P. chlamydosporia research.