Shared decision making (SDM) between clinicians and patients is an integral part of developing true patient-centered care. The principles of SDM are broadly applicable to most clinician–patient encounters, but they may be particularly important in making decisions where the risks and benefits to an individual patient are nuanced. One such example is screening for lung cancer using low-dose computed tomography (LDCT), which may benefit certain patients but also poses a risk of harm due to overdiagnosis. The Centers for Medicare and Medicaid Services mandates SDM using a formal decision aid for reimbursement for lung cancer screening. However, this analysis of transcribed conversations between physicians and patients found almost no use of SDM principles. In particular, physicians universally recommended screening with LDCT, failed to discuss the potential for overdiagnosis, and did not use decision aids or patient education materials. Although limited by a small sample size, this study raises the concern that structural barriers (such as lack of time with patients) and poor understanding of SDM may be exposing patients to harm through limited understanding of diagnostic testing decisions. A related commentary discusses the potential for overdiagnosis of lung cancer if LDCT is used without proper attention to SDM.