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The National Water Commission and Murray Darling Basin Authority are increasing their focus on transparency, risk assessment and uncertainty requirements within the water allocation planning process. Whilst there has been significant development within these areas of research in the last few decades in a general sense, there are few examples of them being applied to groundwater planning and management. To address this gap, in 2011 the CSIRO Water for a Healthy Country National Research Flagship initiated the Groundwater Management Modelling strategic project to develop integrated capability to evaluate groundwater allocation planning options. The objective of this project was to demonstrate how groundwater models together with uncertainty, environmental and socio-economic models provide additional information to water managers for making better decisions about water allocation and management. In this way, the value of the groundwater allocations may be maximised, whilst still meeting resource condition targets (RCTs) such as stabilisation of groundwater levels, protection against seawater intrusion and protection of groundwater dependent ecosystems. This report is a synthesis of the development of each component of the model – groundwater modelling, socio-economic modelling, groundwater trade modelling, uncertainty assessment and the development of a workflow through which to integrate this process. The report presents a case study of the Nowergup region in Western Australia, addressing management scenarios that are currently of concern to the Department of Water (DoW). The work presented describes a first attempt at integrating hydrogeological, socio-economic, groundwater trading models for modelling groundwater management and water allocations. It applies eight different management scenarios to a case study, the Nowergup Groundwater region, Western Australia, using an existing groundwater model, and newly developed socio-economic and groundwater trading models. The outcomes from the hydrogeological modelling using the various management scenarios provided a first step toward being able to indicate the impacts of management strategies on groundwater levels and groundwater dependent ecosystems. It was found that only two, relatively extreme management scenarios were able to meet Ministerial Conditions for Lake Nowergup for part of the year; that is a lake stage higher than 16.3 m. These scenarios included reducing groundwater extractions from the sub-areas surrounding the lake by 50%, and increasing lake supplementation pumping by 5 times the current rate (6 GL/a). Initially these management strategies did not appear to be economically viable. Initial results from the economic and groundwater trading analysis, however, suggested that the socio-economic value of maintaining the lake level at Ministerial Conditions exceeded the cost of supplementation by several orders of magnitude, and exceeded the foregone profits of irrigation surrounding the lake by several times. A key part of this problem is therefore to equitably distribute the cost of maintaining the lake level in order to maximize the overall benefits to the region. Some tradeoffs between urban areas, irrigation and public amenity will be required. Lining the lake bed with a low conductance material, such as clay flocculent will assist in significantly reducing the volume of water required for supplementation. Basic bootstrapping uncertainty analysis showed that there is a very high likelihood that Ministerial Conditions will be met between 10% and 16% of the time over the 40 years, or between 20% and 35% of the time during the last 10 years of modelling. The catchment lag time, or time required for the groundwater system to reach equilibrium is not an insignificant factor in this case study, and should be considered in the management modelling and risk analysis for all groundwater systems. A workflow was developed to integrate and run the individual model components