In the past huge Geo-ICT systems have been developed at high cost. Often the management of such projects was poor and so the time used for development, the amount of personnel and the costs exceeded the planned. Strict management was necessary using a systematic development SDM was one of the first methods that became into use and many variants of it are developed. In order to enable the influence of the organisation’s management that ordered the development and the influence of the future users better, a prototyping method became into use in the eighties. The author describes shortly both systems and his experiences using them