Background: Malnutrition is a complex and costly condition that is common among older adults in the United States (US), with up to half at risk for malnutrition. Malnutrition is associated with several non-medical (i.e., social) factors, including food insecurity. Being at risk for both malnutrition and food insecurity likely identifies a subset of older adults with complex care needs and a high burden of social vulnerability (e.g., difficulty accessing or preparing meals, lack of transportation, and social isolation). US emergency departments (EDs) are a unique and important setting for identifying older patients who may benefit from the provision of health-related social services. This paper describes the protocol development for the Building Resilience and InDependence for Geriatric Patients in the Emergency Department (BRIDGE) study. BRIDGE was designed to assess the feasibility of an ED-based screening process to systematically identify older patients who are at risk for malnutrition and food insecurity and link them to health-related social services to address unmet social needs and support their health and well-being.Methods: Phase 1 efforts will be formative and focused on identifying screening tools, establishing screening and referral workflows, and conducting initial feasibility testing with a cohort of older patients and ED staff. In phase 2, which includes process and outcome evaluation, the screening and referral process will be piloted in the ED. A partnership will be formed with an Area Agency on Aging (AAA) identified in phase 1, to assess resource needs and identify community-based social services for older ED patients who screen positive for both malnutrition risk and food insecurity. Data on screening, referrals, linkage to community-based social services, and patient-reported quality of life and healthcare utilization will be used to assess feasibility.Discussion: The tools and workflows developed and tested in this study, as well as learnings related to forming and maintaining cross-sector partnerships, may serve as a model for future efforts to utilize EDs as a setting for bridging the gap between healthcare and social services for vulnerable patients.