The Chemo-Toxicity Calculator is an 11-item pre-chemotherapy assessment designed to be utilized by clinicians in order to evaluate a patient’s risk of having severe chemotherapy-related side effects. The tool was developed based on results of a study which evaluated 500 older patients with cancer starting a new chemotherapy regimen (Hurria et al. JCO 2011). Our ultimate goal is to utilize this Chemo-Toxicity Calculator in clinical practice, where it can be used as a part of shared decision-making between the physician and patient. A version can be found at: http://www.mycarg.org/Chemo_Toxicity_Calculator.