This article explores the debates that unfolded within Médecins Sans Frontières (MSF) around the decision to launch search and rescue operations in the Mediterranean in 2015. It examines how, beyond the unifying imperative to help, there remained very different political interpretations within the organisation about the proper role of humanitarian actors in tackling this visible and tragic situation. The points of contention included categorisation, feasibility, medical impact, and politics, raising the following central questions: should categories matter, and is it relevant whether a needy person is classed as a camp-dwelling refugee or an irregular migrant at sea? Are the needs in the Mediterranean more serious than those in disasters elsewhere? Would search and rescue operations end up placing publicity and politics over impartiality and neutrality? Looking at how MSF resolved these and other issues can help illustrate the challenges aid agencies face in a world where deaths from large-scale migration are becoming a more common feature of the humanitarian landscape.