quantity and quality issues raise concerns about sustainable use of natural resources in the basin. In particular there are concerns about damages from increasing salinity and reduced flow in the River on built and ecological assets. There is also concern that climate change, increased water taking through farm dam development, increasing use of conjunctive groundwater will exacerbate issues related the quantity of water in the rivers and the groundwater aquifers. Policy approaches to address these issues will require addressing potentially conflicting interests of multiple effected parties in a balanced way. This paper describes a modeling framework being developed for integrated assessment of impacts on diverse stakeholders of options to manage water supply and demand in the Murray Darling Basin. Two models building on the same hydrogeology – agronomic relationships are presented. One is an optimisation approach to modelling irrigator demand for water. The other is a simulation of irrigator and environmental manager behaviour in a stylised Murray Basin model with stochastic supply and price. We demonstrate application of both models to evaluation of environmental water acquisition strategies for the Murray Basin.