The separation of scenarios into distinct alternatives (groups of data) meets one of the basic goals of scenario management: maximizing the number of scenarios you can develop by mixing and matching existing alternatives. Two other primary goals have also been addressed: a single hydraulic model file is used, and easy access to input data and calculated results is provided in numerous formats through the intuitive graphical interface.

In order to meet the objective of minimizing the amount of data that needs to be duplicated, and in order to consider conditions that have a lot of common input, you use inheritance.

In the natural world, a child inherits characteristics from a parent. This may include such traits as eye-color, hair color, and bone structure.