Engineering is the application of science and mathematics to human problems. This is a view that pervades engineering education. Recent emphasis in the United States is ‘engineering is design’. The thesis of this paper is that engineering as science as well as engineering as design are inadequate conceptions of engineering. The thesis is supported by comparing school and out-of-school knowledge. The nature of engineering is explored in terms of the activities of engineers and the goals of engineering education. Koen’s definition of the engineering method, “The engineering method is the use of heuristics to cause the best change in a poorly understood situation within the available resources”, is introduced. The nature of expertise is examined. Alternatives to the ‘empty vessel’ model are presented for the development of engineering expertise. The alternatives include cognitive apprenticeship, reflective practicum, co-operative learning and problem-based instruction.