Viruses infection millions annually, causing severe illness and threatening global public health. Limiting the impact of viral infection requires a multi-layered understanding of viral immunity, from basic research on viral recognition and host immune response, to the clinical applications of novel antiviral and host-targeted therapies and vaccines. Despite recent advances, the mechanisms of both both rapid host recovery as well as severe and fatal disease outcomes, are far from clear. This Keystone Symposia conference will cover a wide range of topics in viral immunity including innate immunity and inflammation, viral sensing and antigen presentation, adaptive T and B cell immunity, novel vaccine development, human immunology across anatomical sites, and innovative computational analyses. Animal models will be examined alongside human and clinical studies, and multi-disciplinary integration will enhance perspectives. A key outcome will be fostering collaborations across different approaches such as viral models and host systems, and across different communities from academia to government to industry. The overall objective of this conference is to provide a unique opportunity for cross-disciplinary interaction and knowledge exchange. Joint efforts in understanding viral immunity are needed for the rational design and development of immunotherapies and vaccines towards seasonal, emerging, and re-emerging viruses.