This thesis examines workforce differentiation, which is the customisation of Human Resource Management practices for different categories of employees such as “talent” or “high potentials”. Workforce differentiation is increasingly common among firms, but its antecedents and consequences are not well known yet. The thesis first investigates on which basis employees are selected into different talent categories. It is hypothesized that “hard” characteristics, such as employee human capital and objective employee status, as well as attitudes towards employer and supervisor, such as person-organization fit and leader-member exchange, predict categorization in a workforce differentiation system. Next, the impact of workforce differentiation on employees' perceptions of organisational justice and turnover intentions is analysed. The results showed that workforce differentiation is positively related to intentions to remain. It is also shown that workforce differentiation affects perceived organizational support via perceptions of overall organizational justice.