In this essay, Christopher Winch explores the relevance of Ludwig Wittgenstein's account of rule-following to vocational education with particular reference to the often-made claim that any account of an activity in terms of rule-following implies rigidity and inflexibility. He argues that most rule-following is only successful when it involves a degree of flexibility. For instance, most technical work that involves rule-following requires flexibility and situational awareness for success. Technical education that fails to take account of the need to apply rules in a way that accounts for a wide variety of situations is likely to be unsuccessful. Winch offers an account of professional judgment based on Stephen Toulmin's theory of argumentation and discusses progression from novice to expert in terms of Toulmin's analysis. He also considers the relation between vocational education and other practices in the context of the wider civic implications of occupational practice.