Throughout history humanity has shaped nature and nature has shaped the development of human society. Social-ecological co-evolution now takes place also at the planetary level and at a much more rapid and unpredictable pace than previously in human history. More land was converted to cropland in the 30 years after 1950 than in the 150 years between 1700 & 1850. Since 1960: Flows of biologically available nitrogen in terrestrial ecosystems doubled Flows of phosphorus tripled > 50% of all the synthetic nitrogen fertilizer ever used has been used since 1985. 60% of the increase in the atmospheric concentration of CO2since 1750. Greater appreciation of the coupled socio-environmental system. Analysis of Land Decision Making. Valuation of Ecosystem Services. Scaling across physical and scientific dimensions of observational systems and methods, case studies, experiments, and model analyses. Vulnerability analysis of multiple stressors from and on the coupled system. Incorporation of historical aspects and timescales of social and environmental changes.