BRIEF BACKGROUNDCollaboration with organizations that advocate for patients with cancer is a critical step in actively partnering with patients and embedding patient engagement in cancer-related research and practice across the cancer care continuum. As novel and potentially highly disruptive technologies are developed, like multicancer early detection (MCED)-bloodbased screening tests designed to identify the presence of more than 1 cancer-advocacy organizations are poised to ensure that patients' needs and preferences inform the development, planning, and implementation of these technologies. MCED diverges from traditional organ-based cancer screening in that it aims to detect any malignant changes throughout the body, providing for an initial screening for cancer in which positive tests would be followed by more focused diagnostic testing. Development of this approach to cancer screening, supported by sound epidemiologic and biologic reasoning, has been vigorously pursued by academic and industry scientists, and emerging performance data are promising. 1 This commentary, specific to patient engagement and advocacy considerations, is 1 of several commentaries included in this special issue of Cancer born out of a Universal Cancer Screening Summit (the Summit) hosted by the Mayo Clinic Cancer Center, the American Cancer Society, and the Union for International Cancer Control in February of 2020. The Summit was the first convening of advocacy and nongovernmental organizations (outside of the private industry developing MCED technology) to shape a global MCED strategy. Each commentary emerged from a key theme discussed at the Summit and addresses a unique aspect of MCED, including: preclinical/clinical research, regulatory approval, advocacy and patient perspectives, international considerations, clinical practice guidelines, modeling analyses to estimate health and economic outcomes, and industry engagement. These commentaries collectively offer the first frameworks for the development, validation, and clinical application, as well as advocacy, related to MCED technologies. The current commentary emerged from discussions of the critical importance of engaging patients in cancer research and development of new screening, diagnosis, and treatment technologies.The goal of this commentary is to begin a conversation about how the delivery of MCED may affect patients and communities, examining 4 domains of access to care 2,3 : acceptance, access, affordability, and accountability. We also summarize patient perspectives regarding existing screening modalities and share initial patient insights about the concept of MCED as an example of how powerful patient partnerships can be in designing health systems and services. The primary objective of this commentary is to bring visibility to the importance of including the patient voice at all stages in the development and implementation of MCED technologies.