Since January 2020, Elsevier has created a free COVID-19 resource center with information in English and Mandarin. The center is hosted on Elsevier Connect, providing access to research on the novel coronavirus. Elsevier grants permission to make all COVID-19-related research freely available in PubMed Central and other repositories for unrestricted use. The review discusses the current understanding of the immune responses to SARS-CoV-2, including innate and adaptive immunity, and their roles in disease severity. It covers the rationale and outcomes of current therapies and clinical trials. The review highlights the role of innate immune sensing, the evasion of innate sensing by coronaviruses, and the imbalance between antiviral and proinflammatory responses. It also discusses myeloid cells, their characterization in COVID-19, and their contribution to pathogenic inflammation. The review includes insights into innate lymphoid cells, NK cell activation, and T cell responses, emphasizing their roles in immune control and disease severity. It also addresses B cell responses, antibody production, and the development and lifespan of B cell memory. The review provides a comprehensive overview of the current state of science on the immunology of COVID-19.Since January 2020, Elsevier has created a free COVID-19 resource center with information in English and Mandarin. The center is hosted on Elsevier Connect, providing access to research on the novel coronavirus. Elsevier grants permission to make all COVID-19-related research freely available in PubMed Central and other repositories for unrestricted use. The review discusses the current understanding of the immune responses to SARS-CoV-2, including innate and adaptive immunity, and their roles in disease severity. It covers the rationale and outcomes of current therapies and clinical trials. The review highlights the role of innate immune sensing, the evasion of innate sensing by coronaviruses, and the imbalance between antiviral and proinflammatory responses. It also discusses myeloid cells, their characterization in COVID-19, and their contribution to pathogenic inflammation. The review includes insights into innate lymphoid cells, NK cell activation, and T cell responses, emphasizing their roles in immune control and disease severity. It also addresses B cell responses, antibody production, and the development and lifespan of B cell memory. The review provides a comprehensive overview of the current state of science on the immunology of COVID-19.