Neonatal hyperbilirubinemia continues to be a leading cause of morbidity and mortality in resource-limited countries. The aim of this study was to measure the effectiveness of existing phototherapy units at a local hospital in Cameroon using an irradiance meter. Phototherapy units (n 1/4 4) in one newborn nursery in Cameroon were evaluated. The average irradiance of the functioning units was 2.87 mW/cm2/nm, which is substantially below the recommended range of 10-30 mW/cm2/nm. With simple improvements, one new prototype unit was developed. Its irradiance was 23.3 mW/cm2/nm. We concluded that irradiance of phototherapy units should be measured, as many local nurseries worldwide may not be delivering effective treatment. Simple and costeffective changes to phototherapy units can make a substantial improvement in irradiance.