The supply of highly qualified scientists, technologists, engineers and mathematicians is perceived by governments globally as being vital in securing economic prosperity, but somewhere along the line pupils are being "switched off", and disengage with the study of science, technology, engineering and mathematics (STEM) beyond compulsory schooling. Improved STEM Education is presented as a way forward, and the supply of well qualified teachers is perceived as integral to achieving this vision. However in England and Wales, as government funded teacher training bursaries rise for those seeking to pursue a career in mathematics or science, funding for those wishing to train to teach engineering or design and technology is less lucrative. As individual disciplines both hold enormous potential to contribute to the STEM agenda, however currently this is not wholly realised. Set against a background of policy reform and curriculum change, this paper seeks to explore the ways teachers of design and technology perceive STEM, and how the range in variation of perception, relates to design and technology pedagogy. Phenomenography is the adopted methodology, and as such this paper explores participant's pedagogical understanding and perceptions from a non-dualistic ontological stance. The primary research tool was interview, which following data analysis, categories of description were formed to create empirically grounded outcome spaces. Outcomes from this study show that teacher's perception of STEM, their personal knowledge, and understanding of that knowledge, is intrinsically linked to the effectiveness of STEM delivery in their own classroom practice. In conclusion, findings from this study would support, in order for learners (pupils) to become STEM literate, that teachers of all STEM subjects be supported to explore ways in which they can best foster mutually reciprocal arrangements with their STEM counterparts.