The chapter summarizes work conducted under the UK National Ecosystem Assessment and the ESRC SEER project. This synthesizes valuation studies of the effects of land-use change on agricultural output, greenhouse gases, open-access recreation, and urban greenspace. All effects are valued in economic terms and contrasted with an assessment of the costs of maintaining present levels of biodiversity. The valuation models are spatially explicit, revealing the effect that underlying variation in the natural environment has on mitigating or exacerbating effects. Various scenarios of change are appraised over an extended period of time. Results suggest that sole adherence to the maximization of market values can lead to net losses when other impacts are assessed. In contrast, changes which emphasize both market and non-market effects can yield substantially greater benefits for society.