Standard inventory planning components within inventory management systems are not fit for purpose when it comes to MRO inventory planning. They are based upon a “Purchase to Consume” model within a manufacturing approach, where parts are purchased according to production planning and then consumed at the end of the process. Planners recognise that this component of their ERP/MRO IT system does not support MRO inventory planning and develop workarounds and separate manual processes external to the system to manage the problem. But this approach lacks the analytical sophistication required to handle the scale, complexity and uncertainty of demand that characterises MRO inventory.