Satisfactory maintenance is crucial for the operation of complex production systems. Insufficient maintenance – potentially due to missing spare parts – can result in breakdowns of the maintained systems, accompanied by cost effects (downtime costs, costly emergency shipments, etc.), diminishing profits, and a declining customer service perception. Thus, the effective and efficient management of maintenance services and the spare parts supply chain is of major relevance for the operation of complex technical systems. Minimizing downtimes of the maintained system while keeping the supply chain costs within an acceptable range can only be achieved by exact forecasts of system breakdowns. Due to the sporadic character of the demand and the broad range of affected system components, the application of “classical” forecasting methods – e.g. for finished products – does not allow for precise demand predictions and causes low forecast qualities. Therefore, more appropriate methods, including advanced embedded diagnostic/prognostic systems, are required to allow for an efficient planning of respective maintenance activities and spare parts replenishment.  Furthermore, supply and distribution of the needed spare parts along the supply chain together with the planning of service personnel are mandatory for effective maintenance.