This article argues that the role of practical work in science is overemphasised and misunderstood. Science is distinguished by the fact that it is a set of ideas about the material world and not by empirical enquiry. The latter is only one of six styles of reasoning that have been used to develop scientific ideas. The lack of clarity around the role of practical work in science means that it is often poorly used in the teaching and learning of science. And, until its role is clarified, attempts to assess it are of little value.