There are multiple dimensions of sustainability, including soil, water, and air quality, greenhouse gas emissions, and energy inputs and outputs. Because many of these elements interact, they should be analyzed using an integrated approach. Because biomass will be produced and consumed in specific locations depending on local biophysical, infrastructure, economic, and social factors, such analysis should be spatially-explicit. Because the various benefits, costs, and trade-offs accrue in different places and at different times, analyses should be conducted at multiple spatial and temporal scales. I will discuss methods for quantifying sustainability with examples from ongoing collaborative research projects at different spatial scales.