This paper assesses the impact of perceived HRM practices on organisational citizenship behaviour (OCB) and whether leader membership exchange (LMX) mediates this relationship. The required research data were retrieved from four different departments within a logistics and supply chain management organisation. The results show that there is a significant relationship between the HRM practices as perceived by a subordinate and their level of organisational citizenship behaviour. The relationship that subordinates have with their frontline manager (LMX) acts as a significant mediator. In the final section, of this paper the findings are discussed and recommendations for future research and practical implications are given.