Mucositis, an inflammation of the mucous membranes, is a commonly occurring side effect of chemotherapy and radiation. Oral mucositis can cause significant clinical consequences, such as pain, malnutrition, and local and systemic infections. Nurses have a critical role in all aspects of managing mucositis, including assessing it, teaching oral care, administering pharmacologic interventions, and helping patients cope with symptom distress. Mucositis can have a negative impact on the overall treatment experience, especially when severe pain or infections occur. Many interventions for managing mucositis exist; however, some are based in tradition or expert opinion and have not been studied in large, randomized, controlled trials. In addition, a variety of assessment tools are available, which creates confusion and difficulties when comparing interventions across studies. This article reviews empirical evidence related to interventions for oral mucositis. Oral care and rinses, pharmacologic interventions, and other techniques are evaluated. Gaps in the literature and opportunities for research, education, and practice changes are discussed.