Background: Oncologists are often reluctant to discuss life-expectancy estimates with their patients because of concerns about their inaccuracy and limited evidence regarding benefits. Objective: Determine oncologist accuracy in predicting their advanced cancer patients' life expectancy and correlates associated with accuracy. Design: Multicenter prospective, longitudinal study of patients with advanced cancer, assessed once at baseline and followed to death. At baseline, patients were asked whether their oncologist had provided them with a lifeexpectancy estimate. Setting/Subjects: Eighty-five patients with advanced cancer recruited from outpatient cancer clinics. Measurements: Patients' baseline sociodemographic and time to death, and clinical characteristics were examined to determine their associations with the accuracy of the oncologists' life-expectancy estimates as recalled by their patients. Results: Seventy-four percent (63/85) of patients recalled that physician life-expectancy estimates were accurate to within a year; estimates were most accurate when patients had 9-12 months to live. Factors significantly ( p < 0.05) positively associated with oncologists' greater accuracy to within a year were the patient's age, recruitment from a community-based oncology clinic, poor performance status, and quality-of-life at baseline. Oncologists' prognoses that were accurate to within a year were associated with greater likelihood of patients, at baseline, acknowledging that they were terminally ill (OR = 12.20, 95% CI = 2.24-66.59), engaging in an end-of-life discussion (OR = 4.22, 95% CI = 1.45-12.29), completing a do-not-resuscitate (DNR) order (OR = 2.94, 95% CI = 1.03-8.41), a lower likelihood of using palliative chemotherapy (OR = 0.30, 95% CI = 0.11-0.85), and clinical trial enrollment (OR = 0.09, 95% CI = 0.02-0.50). Conclusions: Oncologists are able to estimate their patients' life expectancy to within a year. Accuracy to within a year is associated with higher rates of DNR order completion, advance care planning, and lower likelihood of chemotherapy use near death.