A best evidence topic was constructed according to a structured protocol. The question addressed was: In children undergoing umbilical hernia repair is a rectus sheath block (RSB) better than local anaesthetic infiltration of the surgical site, at reducing post-operative pain? From a total of 34 papers, three studies provided the best available evidence on this topic. One randomised clinical trial showed RSB had a better analgesic effect in the immediate post-operative period. In another randomised trial opioid consumption in the peri-operative period was found to be significantly lower in patients administered RSB. These improvements in pain and analgesia consumption need to be balanced against the expertise, training, equipment required, time implications and complications of performing a RSB.