This report provides an account of the debates that took place during a meeting of experts organized by the ICRC in January 2012 in Geneva. The subject of discussion was “Use of Force in Armed Conflicts: Interplay between the Conduct of Hostilities and Law Enforcement Paradigms.” The meeting sought to find the line dividing the conduct-of-hostilities and law-enforcement paradigms in situations of armed conflict. It paid especial attention to non-international armed conflicts, during which the interplay between the two is particularly discernible. The report is divided into three parts. First, it addresses the legal basis and distinguishing features of the two paradigms. Then, it introduces and discusses five case studies pertaining to the use of force; these studies were developed to illustrate some of the concrete legal and practical issues that arise in the field: Case study 1: The use of force against potential targets (example of the isolated sleeping fighter) Case study 2: Riots (where civilians and fighters are blended in with each other) Case study 3: Fight against criminality Case study 4: Escape attempts and rioting detainees Case study 5: Checkpoints The third part explores legal issues relevant before and after the actual use of force – notably questions of planning and investigation. A brief conclusion sums up the points of agreement and the differences of opinion among the experts.