This is the first book on the very important predatory mite family Phytoseiidae of North America and Hawaii. These mites are found on plants, in soil, forest litter and stored products. It includes biology, collection and preparation, distribution, history, host association, morphology, and taxonomy of 428 species belonging to 54 genera, including 4 new genera and 75 new species. This book is very useful for anyone working in biological control and on predatory mites.