Where does planning begin and end as a field of research and action? Answering this question is a challenge, probably even more so in the first case (field of research) than in the second (field of action), so much so that planning is sometimes confused with urbanism, architecture, geography, civil engineering, design (interior and industrial), planning, etc. To this difficulty is added another, that of defining or rather precisely identifying the theoretical frameworks on which planning research is based, which seems to forage here and there rather than rely on a clearly identified corpus. It is in this context that we have drawn on three theses from different disciplines to better define the specificity of planning disciplines. In order to gain a better understanding of the nature and content of theses from different disciplines, we will first present the main epistemological currents, and then focus our analysis on the content of theses from the Faculty of Law, the Faculty of Pharmacy and the Faculty of Planning.