This paper addresses the need to model recharge to groundwater systems at the scale of whole catchments. It looks at developing the right conceptual model of how water moves through a given landscape for both homogeneous and heterogeneous catchments. One-dimensional recharge models and three-dimensional recharge models are considered. Discussion of which recharge modelling approach to use take in consideration of the availability of data, the nature of the questions being asked, and the expertise of the investigators.