The management and associated costs of inventory is an area of increasing concern. In the case study presented in this paper, considerable effort was allocated to managing the stores holdings in a cost effective way. The task remains to continually balance the investment in holdings versus avoiding costs due to not having a spare immediately available. A risk based approach was adopted to assign a level of criticality to a spare to determine whether or not to continue holding it. However, even after establishing a criticality system, it was proven necessary to implement an ongoing audit process which refreshed the required holding levels.