The complexity of water resources systems can often be addressed by applying decision support systems (DSS) and computerised models, which can transparently present the elements of the system and their interrelationships. A DSS for IWRM will typically include a database and processing environment, a knowledge and information system, a modelling and analysis framework, a socioeconomic modelling and analysis framework, and a communication framework. There are many IWRM areas where models and DSSs can inform the process by allowing water managers to better characterise multiple factors and future uncertainties. This Technical Focus Paper provides for guidelines for elaborating and validating modelling/DSS tools to assist decision-makers in implementing IWRM. It is a joint knowledge product of GWP, UNEP-DHI Center, DHI and SIWI.
