DISEASES, the second volume in the four volume set, THE MOUSE IN BIOMEDICAL RESEARCH, departs from the first edition, by discussing specific disease causing microorganisms, rather than the format used in the first edition which discussed infectious diseases affecting specific organs and tissues. As such, the volume consists of 26 chapters subdivided into RNA viruses and DNA viruses, as well as bacterial, mycotic, and parasitic infections. These chapters not only provide updates on pathogenesis, epidemiology and prevention of previously recognized murine pathogens, but also include information on newly recognized disease-causing organisms: mouse parvovirus, cilia associated respiratory bacilli and Helicobacter spp. A separate category, consisting of 3 chapters, discusses zoonoses, tumor pathology of genetically engineered mice, and spontaneous diseases in commonly used mouse strains.