In the social sciences, and particularly in gentrification research, there seems to be a persistent fascination with, and an urge to pursue a course towards synthesising, integrating or uniting very different approaches into a single comprehensive explanation. One concept often raised in this context is complementarity (associated with Bohr's 'Copenhagen interpretation' of quantum mechanics), though usually in an unreflective and uncritical manner. The purposes of this paper are to outline the concept of complementarity; to clarify what we should be careful not to ascribe to the concept; and to provide a rough sketch of what a Copenhagen interpretation of gentrification would involve. It is argued that while it is a worthy task to strive for integration and synthesis in comprehensive thick descriptions, we will have to accept that the theoretical bases for our understanding of various aspects included in these studies may not be so easy to unite into one unambiguous and internally consistent theoretical construct.