Abstract: The practice of public health within military settings presents distinct ethical challenges that differ from those encountered in civilian public health practice. This article explores the unique ethical considerations faced by military public health professionals, focusing on the tensions between individual rights and the health needs of the collective, which is amplified by the military's relative control over the lives of service personnel. The paper applies Upshur's (2002) 'Principles for the Justification of Public Health Intervention'-harm, least restrictive means, reciprocity, and transparency-to the military context, including in combat operations. It examines the 'dual loyalty' dilemma faced by military public health professionals, who hold professional commitments to both their patient population and, as military officers, to the chain of command. Further ethical considerations around defining the 'public' in military settings, access to healthcare, and the risk of moral injury are explored, including examples from previous military operations. The article provides a novel contribution to public health ethics practice by offering an overview from the perspective of public health professionals working within the armed forces which could guide training, policy development, and practice.