Procedures of party leadership selection have attracted considerable scholarly attention in recent years, but voting motives of party members in leadership elections have not been fully studied yet. This paper presents a new model of voting in party leadership elections that is inspired by previous models that were mostly tailored to more exclusive selectorates (such as the parliamentary party). We adopt an inductive research strategy that is based on an open question in member surveys that were held on the occasion of three Belgian party leadership elections. As a result, we obtain a comprehensive model with eight different vote motivations: policy positions, electability, competence, perceptions of personality traits, socio-demographic characteristics, personal relationships, party-organisational reasons and negative voting. Our findings also show that the kinds of motivations that are put forward by members are dependent upon the number of contenders.