There is a lack of clarity as to why some nurses are not delivering optimal pain management to children post-operatively. This retrospective chart review study examined nurses' pain scoring on 175 children during the first 24 hours post-operatively. Data were analysed on the amount of assessments made, assessment scores recorded, as well as the age, gender and type of surgery performed. One-quarter of children had no assessment record of their pain in the first 24 hours post-operatively. When the pain tool was part of an observation chart, nurses recorded more pain scores. Nurses' scoring of children's pain is influenced positively by children under five years of age and those who undergo abdominal surgery. Nurses who had access to one document for recording vital signs as well as pain scores were more likely to assess and record a child's pain score than nurses who had to use a separate chart.