Abstract Delirium, a major cause of falls, can occur in as many as 50% of cancer patients undergoing stem cell transplantation, resulting in up to 14 times greater chance of dying. Delirium risk can be mitigated and many other outcomes of stem cell transplants can be improved through behavioral interventions delivered at the bedside through conversation, imagery, and audio. However, traditional means of delivering these interventions are very labor intensive, difficult to quality control, and difficult to cost-effectively scale to many patients. In this SBIR Fast-Track proposal, we seek to develop a technology-enabled bedside digital relational agent specifically programmed to enhance the well-being, safety, and outcomes of cancer patients undergoing inpatient stem cell transplantation, by supporting them through protocols in the following eight categories: Diet & Hydration, Physical Exercise, Incentive Spirometry, Orientation, Non-Pharmacological Pain & Anxiety Management, Psychosocial Support & Staff Communication, Sleep, and Toileting Assistance. We will then conduct a three-year clinical study, deploying this new intervention to over 200 adult patients across two oncology/hematology units, aiming to observe (compared to a randomized control group) statistically significant reductions in length of stay, incident delirium rate, fall rate, anxiety, depression, and loneliness, with improved overall patient satisfaction and rate of immune system recovery post-transplant. This proposal addresses the major National Cancer Institute portfolio areas of “Technologies for Cancer Control (Behavioral Health Interventions)” and “Digital Health (Mobile Health and Health Information Technology).”