Patients with cancer can experience uncertainty when making treatment decisions. When unaddressed, patient uncertainty can result in decisional conflict and decisional regret. Providers can assist in decreasing these factors by involving patients in the decision-making process. Patients who agree to participate should be informed about their diagnosis, prognosis, and treatment options, including the benefits, the risks and harms, or the option of no treatment. Providers also can help patients to clarify their values, which reveal patient preferences and inform tailoring of care for each patient. When an informed patient's personal preferences align with care decisions, decisional quality is achieved.