In describing the economics of irrigation projects, the report characterized the optimal level of investment in irrigation and in irrigation infrastructure maintenance. It examined both financial and economic views of the optimal level of investment in irrigated agriculture. It also examined some of the historic causes of overinvestment in irrigation compared to investments that limited to ones passing a rigorous economic analysis. While the motivation for this report was a better understanding of the economics of maintaining off-farm irrigation infrastructure, the economic performance of those investments depends essentially on how the additional water produced is managed on the farm.