Obsolescence Strategy The overall BT strategy for obsolescence is as follows: Minimise total cost for obsolescence in a project and fulfil emerging customer requirements with an active management, which includes an OMP. Require and agree on upstream information (from vehicle and transit system building divisions, internal and external suppliers) Plan activities in time to achieve minimum cost for obsolescence. There are two defined strategies for obsolescence treatment, the proactive and the reactive strategy. The adoption of the proactive strategy reduces the probability of obsolescence by applying a selection of the following options explained in detail in [1], chapter 7.4: Design for Obsolescence (e.g. multiple source, reuse ) Technology transparency Obsolescence monitoring Planned system upgrades Lifetime buy