In this book the current knowledge on human cytomegalovirus (HCMV) as a human pathogen is lucidly summarized, bringing the reader fully up to date with current knowledge concerning HCMV and all the known clincial and medical aspects of diseases caused by, and associated with, HCMV. The book is divided into four parts: (I) Human cytomegalovirus and human diseases; (II) human cytomegalovirus infections and the immunocompromised host; (III) diagnosis, treatment, and prevention of human cytomegalovirus and human diseases; and (IV) molecular aspects of human cytomegalovirus. Each part is put together from chapters written by experts in the respective fields, providing basic medical and molecular knowledge in addition to more specific understanding of HCMV infections.