Since the 2016 terrorist attacks in Brussels, the Belgian Defence has undergone a significant shift in operational focus, increasingly taking on domestic missions. This evolution has been reinforced by major crises, such as the COVID-19 pandemic and the floods of 2021, which expanded the military’s presence and visibility in civilian life. This chapter examines the broader transformation, emphasizing how the BAF has moved beyond traditional military roles to assume internal responsibilities, including counter-terrorism, disaster response, and public health support. While this reflects a wider evolution in the military’s role within democratic societies, the chapter focuses specifically on the COVID-19 crisis. In Belgium, the pandemic response emerged within a complex federal governance structure and exposed the lack of a clear legal framework for domestic military involvement, resulting in largely improvised, “ad hoc” arrangements. Despite institutional and financial constraints, the Belgian Defence offered vital support while mobilizing medical personnel, providing logistical assistance, and coordinating repatriations. Ultimately, the chapter highlights the importance of building societal resilience through coordinated responses, emphasizing that effective crisis management relies not solely on the military but on the vital collaboration with civilian and political actors.