In this chapter the understanding of runoff generation processes is further enhanced through process studies. An intense sampling campaign was conducted in the Kaap catchment in the wet season of 2013/2014. Through a hydrochemical characterization of surface water and groundwater sources of the catchment and two and three component hydrograph separations, runoff components of the Kaap catchment were quantified using both hydrochemical and isotope tracers. End-member mixing analysis allowed the identification of the relevant runoff components. Hydrograph separation results showed that runoff in the Kaap catchment is mainly generated by groundwater sources. Relationships between rainfall and runoff were also explored, to further understand the runoff generation mechanisms. Strong correlations were found between antecedent precipitation and direct runoff. Finally, the complexity of runoff processes understanding in the context of semi-arid areas is also discussed.