There is an increased risk of infection in patients with cancer that results in higher morbidity and mortality. Several risk factors can predispose these patients to infectious complications. Some such factors include immunocompromised states like neutropenia, allogeneic hematopoietic cell transplantation, and graft-versus-host disease, while others include immunosuppressive agents like corticosteroids, purine analogs, monoclonal antibodies, and other emerging cancer therapeutics like CAR T-cell therapy. The NCCN Guidelines for the Prevention and Treatment of Cancer-Related Infections address infection concerns that may be observed in these immunocompromised populations and characterize the major pathogens to which patients with cancer are susceptible, with a focus on the prevention, diagnosis, and treatment of major common and opportunistic infections. This paper highlights 2 recently updated sections of the guidelines, namely, infection concerns related to CAR T-cell therapy and antimicrobial prophylaxis recommendations, including vaccination, in patients at high-risk for infections.