The WHO Target Product Profile for in vitro diagnostic tests for serious bacterial infection, including neonatal sepsis, defines the essential and desirable characteristics of tests to support early, accurate diagnosis among infants aged 0–59 days. Designed for both hospital and non-hospital settings, the target product profile aims to guide manufacturers, regulators and implementers in developing accessible, affordable tools that improve clinical decision-making, reduce unnecessary antibiotic use and save lives, especially in low-resource settings where the burden of neonatal sepsis remains critical.