Ovarian cancer is a rare disease that causes tremendous suffering because it spreads insidiously along the intestines and strangulates the bowel in a cement-like substance that blocks normal functioning. Virtually all ovarian cancer patients develop peritoneal carcinomatosis (PC), a severe condition that causes bowel obstructions and buildup of fluid in the abdomen and lungs. Patients live a median of 3-13 months, but undergo frequent emergency department visits, hospitalizations, and surgical procedures. Over one-third are readmitted within 30 days of discharge, and 70% are hospitalized near death. As the disease advances, patients accumulate tubes, lines, and drains – necessitating in-home care by informal caregivers or the patients themselves. 2,5-8 A palliative care intervention is desperately needed to improve patients' quality of life (QOL), reduce caregivers' distress, and prevent burdensome hospital-based care at the end-of-life (EOL). Despite frequent and distressing hospitalizations, there is little research testing palliative care interventions in advanced cancer patients with PC who are undergoing transitions in care. The longterm goal of this proposal is to test an effective and scalable palliative care intervention to improve the QOL of patients with ovarian cancer during care transitions, decrease patient and caregiver distress, and – by improving symptom monitoring and skills training for in-home care – reduce burdensome hospital-based care. Informed by Wagner's Chronic Care Model36-38 and the ADAPT-ITT framework for intervention adaptation,39 we developed BOLSTER (Building Out Lifelines for Safety, Trust, Empowerment, and Renewal), a nurse-led care management intervention that harnesses a novel technology platform to promote patient and caregiver activation, self-management, and support. BOLSTER combines 1) a longitudinal relationship among a nurse, the patient, and her informal caregiver, with structured contacts between office visits; 2) a smartphone-based platform to assess patient symptoms and/or problems managing medical equipment, facilitate selfmanagement, and trigger clinical action between visits; and 3) tailored patient and caregiver symptom management and skills training. We will refine BOLSTER using a phased approach with patients, caregivers, and topical/community experts (Aim 1). We will then assess the feasibility and acceptability of BOLSTER through a pilot randomized controlled trial (RCT) of BOLSTER, and estimate outcome parameters (Aim 2) for a full-scale RCT to test the effectiveness of BOLSTER using an adaptive study design. This project is responsive to PA-18-167 “Palliative Care Needs of Individuals with Rare Cancers and Their Family Caregivers.” Although ovarian cancer is a rare disease, BOLSTER has the potential for high impact because it targets PC, a condition that afflicts approximately 10-15% of all cancer patients worldwide. BOLSTER is innovative in targeting a severely distressed and neglected population during transitions in care and harnessing smartphones to identify and address symptoms before they escalate.