Population health is a function of social and environmental health determinants. Climate change is predicted to bring significant alterations to ecological systems on which human health and livelihoods depend; the air, water, plant, and animal health. Agricultural systems are intrinsically linked with environmental conditions, which are already under threat in much of southern Australian because of rising heat and protracted drying. The direct impact of increasing heat waves on human physiology and survival has recently been well studied. More diffusely, increasing drought periods may challenge the viability of agriculture in some regions, and hence those communities that depend on primary production. A worst case scenario may herald the collapse of some communities. Human health impacts arising from such transition would be profound. This article summarizes existing rural health challenges and presents the current evidence plus future predictions of climate change impacts on Australian agriculture to argue the need for significant augmentation of public health and existing health policy frameworks. The article concludes by suggesting that adaptation to climate change requires planning for worst case scenario outcomes to avert catastrophic impacts on rural communities. This will involve national policy planning as much as regional-level leadership for rapid development of adaptive strategies in agriculture and other key areas of rural communities.