Science and design and technology (D&T) are often linked, either formally in the curriculum or by making connections in and between lessons. There has been much debate about how this linking serves the needs of the two subjects and what, in practice, the actual relationship is, as the current English National Curriculum (DfEE, 1999) identifies them as separate subjects. This is in opposition to an earlier view, that is pre National Curriculum, that they could be treated as one indistinguishable area of learning characterised by problem-solving activities. In this article the authors discuss the whys and hows of linking science with design and technology. (Contains 4 figures and 2 boxes.)