Globally, low birth weight and preterm birth are important causes of neonatal deaths. Newborn foot length has been found to be a simple measure for the identification of low birth weight and preterm birth in studies in Africa and Asia. But no studies have been done in the South Pacific region. Dr. Mengi investigated the diagnostic accuracy of foot length and compared foot length measurements recorded by a researcher with those of trained volunteers. From 12 October 2019 to 6 January 2021, she enrolled 342 neonates born to 335 mothers (80% of those eligible); 21% (72/342) of neonates were low birth weight and 8.8% (30/342) were preterm. The optimal foot length cut-off for low birth weight was 7.7cm (sensitivity 84.7%, 95% CI 74.7-91.2%, specificity 69.6%, 95% CI, 63.9-74.8%) and for preterm birth 7.6cm (sensitivity 76.7%, 95% CI 59.1-88.2%, specificity 69.6%, 95% CI 64.2-74.4%). In 123 babies with paired measurements, 92.7% (114/123) of the pairs were within the 95% limits of agreement. Foot length measurement can identify LBW/PTB newborns but needs appropriate training for successful community implementation. The Neofoot study was a sub-study of the Women and Newborn Trial of Antenatal Interventions and Management (WANTAIM), which is evaluating new interventions to improve mother and newborn health in low-income countries, such as Papua New Guinea. WANTAIM receives support from the UK Medical Research Council, UK Department for International Development, Wellcome Trust, Australian National Health and Medical Research Council and the Swiss National Science Foundation.