Seven factors were found to influence surgeon decisionmaking related to oncology referral, with the magnitude of influence differing depending on their decisional proximity. At the core of surgeon decision-making is the clinical encounter wherein the decision is made. Within this encounter, surgeons consider and negotiate their understanding of (1) indications/contraindications for (neo)adjuvant therapy (e.g., tumor pathology, patient comorbidities/health status) alongside (2) patient beliefs and preferences (e.g., the desire or not for chemotherapy). Surrounding the clinical encounter is a number of important mediating factors: (3) a belief that oncologists are the experts, (4) knowledge of local standards of care, and (5) consultation with oncology colleagues. When making decisions about oncology referral, surgeons were also acutely aware of the outer context in which these decisions occur, including (6) system resources and capacity (e.g., access to staging investigations, technology to facilitate coordination of care) and (7) a need to navigate patient logistics (e.g., drug coverage, transportation/lodging). While factors within this outer context infrequently influence referral decisions in a direct way, they often make dealing with the decision more difficult.