This research project considers thirteenth-century burghership within specific social tensions which characterized this century. Flemish urban societies in the thirteenth century were subjected to profound transition in economic, political, social and cultural ways. Within these changing environment the phenomenon of burghership was shaped and interacted with this transition. This research project frames thirteenth-century burghership within three fields of tension: (1) the broad and strict sense and use of ‘burghership’; (2) burghership within the triangular relationship between prince, urban commune and individual town-dwellers; (3) the roll of burghership within two seemingly paradoxical tendencies, namely social polarization and social mobility. The method to achieve these goals will be in the first place a comparative analysis of different Flemish cases. In order to effectuate this analysis, a discourse analysis, a lexicographic analysis and a qualitative approach of the information will be applied.