Background: Information on an individual's risk for death following dialysis therapy initiation may inform the decision to initiate maintenance dialysis for older adults. We derived and validated a clinical risk prediction tool for all-cause mortality among older adults during the first 6 months of maintenance dialysis treatment. Study Design: Prediction model using retrospective administrative and clinical data. Setting & Participants: We linked administrative and clinical data to define a cohort of 2,199 older adults (age >= 65 years) in Alberta, Canada, who initiated maintenance dialysis therapy (excluding acute kidney injury) in May 2003 to March 2012. Candidate Predictors: Demographics, laboratory data, comorbid conditions, and measures of health system use. Outcomes: All-cause mortality within 6 months of dialysis therapy initiation. Analytical Approach: Predicted mortality by logistic regression with 10-fold cross-validation. Results: 375 (17.1%) older adults died within 6 months. We developed a 19-point risk score for 6-month mortality that included age 80 years or older (2 points), glomerular filtration rate of 10 to 14.9 mL/min/1.73 m(2) (1 point) or >= 15 mL/min/1.73 m(2) (3 points), atrial fibrillation (2 points), lymphoma (5 points), congestive heart failure (2 points), hospitalization in the prior 6 months (2 points), and metastatic cancer (3 points). Model discrimination (C statistic = 0.72) and calibration (Hosmer-Lemeshow chi(2) = 10.36; P = 0.2) were reasonable. As examples, a score <5 equated to12 predicted that more than half the individuals would die in the first 6 months. Limitations: The tool has not been externally validated; thus, generalizability cannot be assessed. Conclusions: We used readily available clinical information to derive and internally validate a 7-variable tool to predict early mortality among older adults after dialysis therapy initiation. Following successful external validation, the tool may be useful as a clinical decision tool to aid decision making for older adults with kidney failure. (C) 2016 by the National Kidney Foundation, Inc.