This edition of Current Topics in Microbiology and Immunology examines the role of chemokines and chemokine receptors in host defense and disease development following viral infection. Chemokines represent a family of over 40 small proteins that, for the most part, are secreted into the environment and function by binding to G protein-coupled receptors (GPCRs) that are expressed on numerous different cell types. When initially identified close to 30 years ago, these molecules were associated with various human inflammatory diseases and it was recognized that expression may be integral in leukocyte recruitment to inflamed tissue. There are now four sub-families of chemokines identified based on defined structural criteria relating to the positional location of conserved cysteine residues within the amino-terminus of the protein. Chemokines are now recognized as important in numerous biological processes ranging from maintaining the organizational integrity of secondary lymphoid tissue to participating in various aspects of both innate and adaptive immune responses following microbial infection. With this in mind, this book highlights the functional roles of chemokines and their receptors in participating in various aspects of the immune response against well-known viral pathogens.