Moomba is the largest gas field discovered to date in the Cooper Basin. Eighteen wells have been drilled to evaluate and develop its resources; three into the smaller northern culmination, and the other fifteen into the southern culmination. Gas production is from the Toolachee Formation and Daralingie Beds. Minor, as yet undeveloped, reserves occur in the Patchawarra Formation. The Daralingie Beds are interpreted to have been deposited during a lacustrine regression. Reservoirs exist in delta front sheet sands. The Toolachee Formation can be subdivided into three units whose depositional environments grade upwards from deltaic plain, through alluvial floodplain, to a senile landscape dominated by lakes and coal swamps. The controls on pay sand distribution within the field are complex. They depend on the interplay between structure, lithology, water saturation and porosity / permeability variations. There is no uniform base level of pay, due to the low degree of interconnection between reservoir sands. Studies should be carried out to learn the cause(s) of variation in porosity and permeability. Trends in gas deliverability from the reservoir sands should be mapped and the controls on these trends understood. Two appraisal wells are required. These will not only boost the gas reserves of the field, but also throw light on the distribution of pay within the Patchawarra Formation, map the extent of high productivity sands in the Daralingie Beds, and provide more well control with which to define Toolachee Formation field limits.