<p>Sepsis is a complex process defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. It is associated with significant morbidity and mortality in both adults and children, and emphasis has been placed on its early recognition and prompt provision of antimicrobials. Owing to limitations of current diagnostic tests (i.e. poor sensitivity, delayed results), significant research has been conducted to identify sepsis biomarkers. Ideally, a biomarker could reliably and rapidly distinguish bacterial infection from other, non-infectious causes of systemic inflammatory illness. In doing so, a sepsis biomarker could be used for earlier identification of sepsis, risk stratification/prognostication, and/or guidance of antibiotic decisions. In this Minireview, we review one of the most commonly clinically used sepsis biomarkers, procalcitonin, and its roles in sepsis management in these three areas. We highlight key findings in the adult literature, but focus the bulk of this review on pediatric sepsis. The challenges and limitations of procalcitonin measurement in sepsis are also discussed.</p>