The book "Neonatology and Blood Transfusion" offers a comprehensive collection of insights and research findings presented during the 28th International Symposium on Blood Transfusion in Groningen. It highlights the unique challenges and needs of newborns, one of the most vulnerable and least studied populations in the field of blood transfusion. The contributions in this volume cover a wide range of topics, from developmental immunology to the molecular foundations of hematopoiesis, as well as the physiological aspects of bleeding and thrombosis. The authors emphasize the need to expand knowledge about the unique physiology of newborns while always adhering to the principle of "Primum non nocere" (First, do no harm). The gathered information is not only significant for professionals in the field of neonatology but also for anyone dealing with the risks and benefits of blood transfusions and future therapies.