Zarnekow, RüdigerBrenner, WalterScheeg, Jochen2018-01-162018-01-1620042004https://dl.gi.de/handle/20.500.12116/12406IT management focuses on planning and developing new IT solutions. The importance of production (operation, support, maintenance) and further development of existing solutions is often neglected, although these tasks are responsible for the majority of today’s IT costs. The paper introduces a life cycle model for IT application systems and presents the results of a survey of the life cycle costs of 30 IT application systems. Within the survey, the distribution of costs over the application life cycle was recorded and evaluated. The results show the central importance of recurring costs for production and further development. For a production time of 5 years these costs amounted to 79% of all life cycle costs, whereas only 21% of the costs were incurred during the planning and initial development stages.IT Application SystemsIT ManagementIT ProductionLife Cycle CostsSoftware DevelopmentTotal Cost of OwnershipText/Journal Article1861-8936