This paper discusses a much-neglected aspect of Neil MacCormick's theory of legal reasoning, namely what he calls ‘consequential reasoning’. For MacCormick, consequential reasoning is both an omnipresent feature of legal reasoning in England and Scotland, as well as being a valuable one. MacCormick articulates the value of consequential reasoning by seeing it as contributing to the forward-looking requirement of formal justice, ie, of deciding the instant case on grounds that one is willing to adopt when deciding future similar cases. This paper situates consequential reasoning in the overall picture of legal reasoning MacCormick develops in Legal Reasoning and Legal Theory, going on to show the evolution of his view on consequential reasoning in later work, which culminates in Rhetoric and the Rule of Law. It is argued that MacCormick's later view of consequential reasoning, ie, of a process of testing possible rulings by evaluating the acceptability or unacceptability..