Sepsis in pediatrics continues to be a worthy cause of morbidity and mortality worldwide. Clinical studies and development of consensus have allowed defining it as a clinical condition triggered by an infection leading to life-threatening organ dysfunction. Here we summarize the new diagnostic criteria (Phoenix score), which were elaborated by an international group of experts using three pillars: an international survey, a systematic review with meta-analysis, and the design of a multicenter database, which was used to derive and validate set of criteria with the best predictive profile. Likewise, we review the state of the art of sepsis in pediatrics, the projections of the use of new criteria that define it and the possible role of the use translational medicine.