PROJECT SUMMARY/ABSTRACT In 2017, 2.5 million children died in the first month of life. An estimated 2 million of these deaths could have been prevented by provision of essential newborn care at home and rapid identification of illness and care-seeking by the caregiver. Community health volunteers (CHVs) are a large cadre of lay health workers whose role is to promote access to preventative care and treatment in resource-limited settings. In Kenya, CHVs conduct monthly home visits to pregnant and postpartum women to provide education and screen for complications. Several counties in Kenya have adopted a digital community health toolkit (dCHT) that supports CHV workflow by tracking clients, managing tasks, and guiding home visits. Standardized CHV home visits expand mothers’ access to information and support, however the concentrated risk of neonatal illness in the first weeks of life and its potential to rapidly deteriorate mean that even monthly home visits leave mothers and neonates in need of on-demand support. Our team developed an interactive SMS text messaging intervention, Mobile WACh Neo (NEO), that connects mothers with healthcare workers remotely in the high-risk period immediately following birth to improve maternal and neonatal health. NEO sends automated, theory-based, actionable daily messages that systematically guide mothers to evaluate neonatal danger signs, and facilitates real-time dialogue with a healthcare worker to triage medical concerns and augment maternal social support. The overarching goal of this proposal is to integrate NEO interactive SMS into the existing digital infrastructure supporting CHV workflow in Western Kenya (dCHT) to enable remote communication by mothers with CHVs between home visits. We propose the following specific aims. Aim 1: Employ a human- centered design approach to develop a NEO interactive SMS module in the dCHT, named CHV-NEO. Aim 2: Evaluate CHV-NEO’s impact on neonatal mortality, clinic visit attendance, and caregiver provision of essential newborn care (cord care, thermal care and initiation of breastfeeding), in a pragmatic cluster-randomized trial. Aim 3: Determine the effect of CHV-NEO on CHV and supervisor workflow, and evaluate determinants of CHV- NEO’s acceptability, adoption and fidelity of use. We hypothesize that this innovative strategy will be successfully implemented within existing CHV infrastructure and will improve provision of at-home preventative care, increase timely referral of neonatal illness to facilities, and reduce neonatal mortality. CHV-NEO has potential to address a critical gap in efforts to improve neonatal health in resource-limited settings. Completion of these aims will generate a ready-to-scale intervention and rigorous data on both its effectiveness and the enablers of its successful implementation.