This publication provides systematic catalogues of eight families of scale insects for the world. Cerococcidae (ornate pit scales) including 72 valid species in 3 genera, Halimococcidae (pupillarial palm scales) including 21 valid species in 5 genera, Kermesidae (gall-like scales) has 91 species in 10 genera, Micrococcidae (Medi-terranean scales) with 8 species in 2 genera, Ortheziidae (ensign scales) has 162 species in 11 genera, Phenacoleachiidae with 2 species in 1 genus, Phoenicococcidae (palm scale) with 1 species in 1 genus, and Stictococcidae with 15 species and 3 genera. Several scale insects in these families are serious agricultural pests and others pose a threat when (if) they are introduced into areas outside of their natural habitats. This book is a synthesis and catalogue of all of the taxonomic information published on these families worldwide up to May 2003, plus a few major works in 2004. It gives information on their scientific names, common names, synonyms, host plants, distribution, biology, economic importance, diagnostic features, keys for identification, and published references. This information will benefit all who are interested in the control, ecology, life history, pest exclusion, and pest management of these scale insects including homeowners, nursey personnel, quarantine specialists, extension agents, and state and university researchers.