PURPOSE To increase awareness, outline strategies, and offer clinical guidance on navigating the complexities of treatment planning amid antineoplastic drug shortages. METHODS A multidisciplinary panel of oncologists, ethicists, and patient advocates was assembled to provide rapid clinical guidance to help providers navigate appropriate patient care in cases where rationing or alternative therapies must be considered. The groups of content experts developed general principles for resource allocation during shortages and clinical guidance on alternative therapies for specific disease sites. The recommendations are supported by evidence when available. RESULTS A total of 44 volunteers with content expertise formed the Advisory Group that developed general guidance on the prioritization of antineoplastic agents in limited supply. Disease site–specific clinical guidance was then produced by subgroups on the basis of members' specialties and expertise. The majority of alternative treatment options were developed in consideration of cisplatin and carboplatin shortages. All guidance is posted on ASCO's website. RECOMMENDATIONS The prioritization of antineoplastic agents in limited supply should be based on specific goals of the therapy where evidence-based medicine has shown survival outcome and life-extending benefit in both early and advanced stages. Recommendations for specific disease sites are presented. While management options vary according to the disease site, alternatives are presented. For settings in which there are no alternatives with comparable efficacy and safety, it is recommended that patients are referred to an area where the necessary drug is available or can be obtained. Additional information is available at asco.org/drug-shortages .