This study examines the use of polemical strategies in the internal Franciscan debates during the first half of the fourteenth century, focusing on the exchanges between Ubertino of Casale and his opponents during the Spiritual crisis, and between Michael of Cesena and Gerald Odonis in the aftermath of the so-called theoretical poverty controversy. By comparing the use of polemical tropes and patterns across the two conflicts, it is possible to isolate some of the strategies used by the participants in the debates, as well as highlighting the shifting boundaries of inclusion and exclusion in the definition of what constituted a »true« Franciscan. While outsiders contributed to the debates, this article focuses particularly on the ways in which members of the Franciscan order responded to challenges posed to the authors' understanding of the Franciscan vocation by other members of the order. All sides in these debates agreed on poverty and obedience as central values of the Franciscan life, but they did not accept that their opponents might share their regard for the order's rule and vocation. The debates therefore produced overlapping and competing visions of the Franciscan life which personalised and polarised the underlying larger issues, as well as estab lishing and defending the boundaries between »true« and »false« Franciscans, and there by creating and reinforcing a sense of identity against those members of the order which fell outside the vision.