In the past several years, there have been many new developments in technology applied to the study of early events of virus infection. The purpose of this Conference is to provide a timely forum for the exchange of information and ideas pertaining to the diverse strategies of virus entry into cells. Attachment, penetration and uncoating of genomes of enveloped and non-enveloped animal viruses will be presented and discussed. Topics of major interest to be considered include: a) the nature of the receptors for attaching viruses and progress made toward the purification of receptors; b) virion attachment proteins that react with receptors on the cell plasma membrance; c) post-attachment events, i.e., fusion and virion modification leading to penetration; d) endosomes, receptosomes and lysosomes in viral genome uncoating; e) correlations between the specificity of attachment, penetration and uncoating and patterns of pathogenesis; f) inhibitors of virus entry into cells and their application in animal models; g) use of anti-idiotype antibodies as probes for receptor distribution; h) selection of virus variants (host range) by variant receptors; and i) role of receptors in a cellular function. An extraordinary group of speakers has agreed to participate at the Conference and full attendance by an audience of working scientists and graduate students is anticipated.