This book is dedicated to the scientists whose professional devotion and accomplish­ ments in research on scale insects of the area made the compilation of this book possible. This book has two primary objectives: (1) to enable interested workers, who are not specialists of scale insects, to recognize and indentify these to families, genera and species; and (2) to provide information on the life cycle, host-plant range, natural enemies, geographical distribution, economic importance for each known species from Central Europe, and to provide a bibliography on each taxa covered. Scale insects are important pests of fruit and nut trees, forest vegetation, woody ornamentals, greenhouse and indoor plants. World-wide losses and increased production costs attributed to scale insects are estimated to reach $5 billion annually. It is difficult to recognize them because of their microscopic size and hidden habits. Identification of pest species enables plant growers to check appropriate reference sources for biological information and to select control methods.