On 6 September 2017, Professor Emeritus Frits Kalshoven passed away at the age of 93. I learned about his passing the day afterwards, and although in some ways it should not have come as a complete surprise given his age, it had a very deep emotional impact on me. This was not only from the perspective of an international humanitarian lawyer, since in this moment we lost one of the most respected scholars of the field, someone whose expertise as an academic as well as whose impact as a practitioner can only be described in the highest praise. The great Jean Pictet wrote in his foreword to the Liber Amicorum for Frits Kalshoven that he stands in the long tradition of Dutch legal scholars ‘who, since Grotius, have greatly added to the fame of their country throughout the world’. But an even more important reason for this great feeling of loss was that we had to say good-bye not only to a great scholar, but also to a wonderful human being, a role model, a true humanitarian, a man who despite his numerous achievements remained humble and kind until the end, someone who inspired generations of colleagues, experienced lawyers and young students, in their way to apply, research and disseminate International Humanitarian Law.