Project Summary/Abstract When medically indicated, cesarean birth saves maternal, fetal, and neonatal lives. Historically, the World Health Organization (WHO) recommends a 10 – 15% population cesarean birth rate, among all global populations; some authors suggest 9 – 19% is more appropriate. Therefore, as an evidence-based intervention to prevent adverse pregnancy outcomes, cesarean birth rates of under 2%, which is the case in rural Southwest Ethiopia, is an unacceptable public health problem. Low cesarean birth rates plague many regions of sub- Saharan Africa, so the context of rural Southwest Ethiopia is likely generalizable to many other settings that experience unacceptably low cesarean birth rates. Barriers to proper use of cesarean birth as an intervention to prevent morbidity and mortality in sub-Saharan Africa include those described by the Three Delays Model: 1) the delay in the decision to seek care, 2) the delay in reaching appropriate emergency obstetrical care, and 3) receiving adequate care when the facility is reached. Preliminary data from our target community in Southwest Ethiopia found that the Three Delays is representative of barriers to accessing cesarean birth, which make it “virtually impossible” for many women to reach essential emergency obstetric care. No intervention has yet determined the most effective way of delivering cesarean birth to rural underserved and low-resource regions of sub-Saharan Africa, even though the Three Delays model was published 25 years ago. As such, there is an implementation gap in determining how best to provide cesarean birth in the face of the Three Delays in vast regions of the African continent. Mobile surgical units have been successfully used in Latin America to deliver gynecologic surgery and Médecins Sans Frontières provides cesarean birth in surgically equipped tents in low-resource and war-torn settings. Our overarching hypotheses are: 1) the cesarean birth surgical disparity in rural Ethiopia can be addressed by the implementation of a novel, mobile community-based cesarean birth center staffed by mid-level providers, and 2) the pre-implementation methods we will use to explore (AIM 1), prepare (AIM 2), and design (AIM 2) the center for eventual implementation, dissemination, and adaptation will be generalizable to other settings and/or surgical disparities in sub-Saharan Africa and potentially globally. This proposed work will have impact because it studies how best to deliver cesarean birth to regions of the world that have not ever had access to this life-saving surgery. It will advance knowledge in the field of implementation science because it studies the pre-implementation of a novel and innovative clinical solution to a cesarean birth disparity using Exploration and Preparation aspects of the EPIS framework, and implementation methods that will be generalizable to other settings and conditions where highly innovative, decentralized, pragmatic solutions may be necessary.