The main goal of Integrated Watershed Management is to come to a sustainable resource management in order to sustain or improve the living conditions of the local population [1].

Therfore, watershed manager have to make wise decisions. A sound understanding of all environmental factors within a watershed and their interactions are consequently neseccary.

Thus, the basics about the ecosystem “watershed” are explained in this module. The physical-geographical factors (e.g. precipitation, soil and soil erosion etc.) as well as the human factor and his influence on the environment are discussed in the different modules.