The extent of a regional block for Caesarean section must be tested and documented before surgery commences. In recent years a block to ‘touch’ that includes T5 has increasingly been considered the best predictive test for a pain-free Caesarean section. Our survey examines the consistency with which different anaesthetists identified the location of the T5 dermatome. Seventy-three anaesthetists were asked to mark a point on an anatomical picture to indicate where they would test for T5. Overall there was good agreement on the location of the T5 dermatome, but one in seven anaesthetists were inaccurate by two or more dermatomes. There were no statistically significant differences between the subgroups of senior house officer, specialist registrar and consultant anaesthetists. The knowledge of relevant dermatome levels should be an integral part of obstetric anaesthetic training.