Neonatal sepsis is a major cause of death in infants and young children in low-income and middle-income countries. There is increasing concern that rising antimicrobial resistance is reducing the effectiveness of recommended antibiotic treatments. New studies are being set-up to test new approaches to manage this condition, but are hampered by lack of information about what values of common blood tests are seen in infants in hospital. In this study, we will describe what values are seen in infants in Oxfordshire, to provide “background” information which will help us work out how to assess values that we see in new research studies.