The proceedings of the July 1989 Symposium are organized within 13 chapters: the spike (S) glycoprotein, the haemagglutinin-esterase (HE) and membrane (M) glycoproteins, B- and T-cell epitopes of the structural proteins, expression and immunogenicity of the structural proteins, the nucleocapsid (N) protein, the polymerase and other non- structural proteins, transcription and replication, aspects of coronavirus variation and evolution, porcine respiratory coronavirus, turkey and bovine coronaviruses, non-neurological diseases, neurological consequences of murine hepatitis virus infection of mice, and neurological consequences of murine hepatitis virus infection of rats.