Coccinellids have been very actively studied in the course of the twenty three years since "Biology of Coccinellidae" was published. The great amount of new, and often very important findings have made the previous book outdated and a new synthesis is needed. No other monograph of similar focus and extent has appeared. Iablokoff Khnzorian's "Les Coccinelles" (1982), limited to the tribus Coccinellini, and Gor don's "The Coccinellidae of America North of Mexico" (1985) both concentrate on taxonomy. Majerus' beautiful "Ladybirds" (1994) deal specifically with British coc cinellids and address chiefly amateur naturalists. The focus and the title of the recent book are slightly different from the 1973 vol ume. If a satisfactory comprehensive review of important new findings is attempted, the book would grow too much, due also to References and Indexes. To keep the vol ume at a tolerable extent, the section on larval identification of Palaearctic species has been omitted; not much could be added to the previous version of that part, any way. However, we have kept Kovar's chapter on morphology and anatomy, because of its relation to feeding and other ecological aspects. The chapter on phylogeny was updated also by him. Our Polish friend, Piotr Ceryngier, who has recently specialised in parasites, updated perfectly the parts on parasites and pathogens in Chapter 8. We would be glad if their contribution is quoted by their names. It seems to us that the remarks, contained in the reprinted preface to the previous volume, remain pertinent today.