This chapter presents conditions and effects of User Systems Development using a Spreadsheet Program. It argues that User Systems Development using a Spreadsheet Program is characterized by integration, interactivity and capacity of questioning, which make it possible to control continuous changes in the environment of an organization. Three empirical studies have been carried out using a Grounded Theory influenced approach. The results are presented with the use of the model of generic practice (the ToP model), in order to systemize empirical findings and related theory. The model is used to specify the conditions and results of a specific practice, e.g., a controller practice or an information technology (IT) specialist practice.