The annual Transatlantic Workshop brings together academic, military, and government experts to discuss current challenges in international humanitarian law. The 2019 workshop took place seventy years after the adoption of the Geneva Conventions. This provides an opportunity to engage in some big picture reflections on the development and implementation of the law of armed conflict. Day one focused on current challenges relating to law-making and compliance with the law of armed conflict. Day two examined the application of the law of armed conflict in contexts where other bodies of law might also be applicable.