Abstract Introduction: We aimed to identify and explore the ethical challenges for UK military medical personnel deployed to the Ebola outbreak. Method: Qualitative study using semi-structured, face-to-face and telephone interviews with 20 military personnel deployed between October 2014 and April 2015 in one of three roles: clinician, nursing and nursing assistant, other medical support work including infection control and laboratory and mortuary services. Results: Many participants felt morally motivated. A minority felt negatively about deploying, others that deployment was part of military service. Almost all had initial concerns about their personal safety but were reassured by pre-deployment training. Risk perceptions were related to military service. Patient care was affected by efforts to minimise risk. Significantly, some thought the humanitarian nature of the mission justified tolerating greater risk. Trust in the organisation and colleagues was expressed; many participants referred to the obligation of the chain of command to protect those under their command. There were strong reactions to the perceived low bed occupancy: more patients could and should have been treated. Points of reference for participants' values were previous deployment experience, previous UK/NHS experience, professional values and distinctly military values. Conclusions: Concerns about risk were allayed by 'drills and skills' and trust: lessons here for civilian organisations? Participants expected to be overwhelmed: 'empty beds' presented a significant and pervasive ethical challenge. Participants expressed specific military values that might not be shared non-military workers but had humanitarian motivations that give them common purpose with civilian responders. External funding details ESRC ES/M011763/1