The following presentation examines the role of the Russian military medical service in the ongoing Russian invasion of Ukraine. Russian military medical lessons learned are valuable because Russian forces use NATO and US organization and standards for point-of-injury care, unit types, and wounding classification, making comparisons to US capabilities and concepts of employment possible. Therefore, this presentation seeks to answer the following research question: What are the preliminary military-medical lessons the Russian medical service is learning in Ukraine regarding casualty care? Hence, this presentation describes the challenges the Russian medical service has encountered in Ukraine and examines policy changes by the Ministry of Defense to Russia’s battlefield organization to optimize limited resources and casualty care. In Ukraine, the Russian medical service found itself unprepared to provide effective casualty care with limited resources while conducting large scale combat operations. According to authoritative figures in the Russian military medical service, operating in a battlefield riddled with drones and real-time intelligence, surveillance, and reconnaissance, along with material shortages has put the evacuation of medical casualties at risk. We argue that to deal with these challenges, Russian military medical forces have evolved to be modular and interchangeable. Russian military medical forces have started to task-organize medical responses, mixing and matching across force elements and roles of care. The consequence of these actions and battlefield conditions is less standard force elements and particularly blurred definitions of roles 2 and 3. To conduct this study, we conducted a systematic survey military-defense periodicals from 2022-2025 along with legislation, open-source interviews with Russian military-medical personnel by Russian news media, and a set of telegram posts. We compiled the sample by filtering the articles through a set of key words that included: medical, doctors, hospital, evacuation, and medicine. We then catalogued and categorized the data according to a set of subquestions to conduct a structured analysis. . The questions for the structured analysis are the following: - How is the Russian medical service organized in Ukraine? - Has the organization of the Russian military medical service in Ukraine changed? - What are the challenges the Russian medical service has encountered in Ukraine about casualty care? - What are the proposed mitigations to meet these challenges according to authoritative figures in the Russian military-medical community regarding casualty care? Through these questions, we assembled the data into key themes to answer the main research question.