The 2013 Viruses and Cells Gordon Research Conference, the premier conference in the field, will address key questions in virology: viral infectious cycles, virus/cell interactions, the host immune response and viral immune evasion, pathogenesis, and the development of antiviral therapeutics and vaccines. The meeting will be held at Il Ciocco, the beautiful GRC conference site in Barga, Italy, from May 5-10, 2013. Invited speakers will present new findings on the determinants of viral host range and tropism, the cell biology of viral entry and assembly, the diverse mechanisms of viral replication, the impact of viral infections on key cellular processes and organelles, the innate and adaptive immune responses to viral infection and the counteracting viral mechanisms of immune evasion, the innate and adaptive host responses to infection, viral pathogenesis, and the development of antiviral therapeutics and vaccines. Session conveners, who are experts in the topics covered in each session, will lead lively discussions following each presentation. In addition to the invited speakers, shorter talks will be chosen at the time of registration from the abstracts submitted for the poster sessions. Selections will be made to highlight exciting new developments in virology research with an emphasis on younger scientists. The evening poster sessions are a prominent part of this conference and will provide an important opportunity for participants to present and discuss their research findings in an informal and congenial atmosphere. The conference will bring together investigators at the forefront of the field, young investigators launching independent research careers, postdoctoral fellows and graduate students, and investigators from industry to discuss new ideas and foster collaborations.