How a sample of university educators described STEM, expected outcomes of STEM, expertise of STEM educators, and STEM learning environments were investigated through drawing- and text- based responses. Data were examined by applying the "Legitimation Code Theory (LCT) Specialisation" plane (Maton, 2014). Participants generally held "knowledge-code" (epistemic relations are foregrounded) or "mixed-code" (sometimes epistemic and sometimes social relations are foregrounded) perceptions. Further analysis showed that participants value both disciplinary knowledge and discipline-related practices such as analysing data and providing evidence-based discussions. The LCT approach has been found powerful in its ability to represent the kind of knowledge that might be valued, and the kind of knowers that might be desired by educators of STEM or individual STEM disciplines including mathematics.