This European Standard provides a generic description of the maintenance process. It specifies the characteristics of all the processes, parts of maintenance process, and establishes a maintenance model to gives guidelines for defining indicators.This European Standard is applicable to all organizations (company, institution, agency, etc.) in charge of maintaining physical assets. Therefore, it has been established without a particular organization in mind and does not aim to propose one. This description could be adapted based on the type and size of organization chosen to perform the maintenance, the complexity of the systems maintained and the scope of the external contracted services.The purpose of the breakdown into processes and the representation of their inter-relationships is to help maintenance personnel, and particularly management at different levels, to:-clearly identify the actions to be taken in order to meet the overall objectives set by Management in terms of maintenance;-delegate responsibilities that ensure the realization of the actions with the required performance levels;-for each process, clearly determine:a)the necessary inputs and their origin;b)the required results and their intended uses;-monitor and quantitatively assess the performance obtained at various levels of the breakdown into processes;-improve the collection and the distribution of data.This standard does not cover software maintenance itself, but applies to items containing software.