Urban morphology is a thriving field of enquiry involving researchers from a wide diversity of disciplinary, linguistic and cultural backgrounds. While this diversity has helped advance our understanding of the complexity of urban form, confusion and controversy has also arisen over the various theoretical formulations forwarded by researchers from different philosophical and epistemological backgrounds. With the aim of improving intelligibility in the field, this paper proposes a straightforward scheme to identify, classify and interpret, or ‘map’, individual contributions to the study of urban form according to their respective theoretical or epistemological perspectives. Drawing upon epistemological discussions familiar to the readers of this journal, the authors first distinguish between cognitive and normative studies. A second distinction is made between internalist studies that consider urban form as a relatively independent system, and externalist studies in which urban form stands as a passive product of various external determinants. Using these basic criteria, it is possible to interpret and synthesize a multitude of contributions and map them using a simple Cartesian grid. The paper highlights how contributions from seemingly different theoretical approaches to urban morphology are intrinsically similar in their treatment of urban form as an object of enquiry.