Remarkable differences in housing policies and dominant forms of tenure can be observed across countries. To what extent are these differences dictated by major vested interests, and explained by ideology in the context of broader political and socio-economic circumstances? Assuming that the comparison between northern and southern European countries has been largely neglected in comparative housing literature, by using the Danish and Portuguese cases I test Kemeny’s typology of rental systems to explain the divergence between these two housing realities. The empirical evidence presented in this paper emphasizes the relevance of Kemeny’s theories in explaining many of the divergent features of these housing systems, but suggests some adjustments, based upon the differences between Kemeny’s theories of dualist rental systems and what was found in the Portuguese case, which aim to expand its explanatory power.