This analysis sheds critical light on the issue of legal certainty in the aftermath of the Supreme Court decision of Smith v Ministry of Defence. This article suggests that the outcome of the case is correct, despite the uncertainty created by the decision to leave the matter of duty of care unclear on the facts. The purpose of this article is to firstly, examine the position of the doctrine of combat immunity in tort of negligence prior to the Smith case. Secondly, to analyse the Smith case and its impact on combat immunity. Thirdly, to examine the policy issues arising as a result of this decision.