Humans are changing the Earth’s biophysical system — atmospheric and ocean climatology and chemistry, extent of snow cover, permafrost and sea-ice, glacier, ice-sheet and ocean volume, and indeed the hydrological cycle. Some changes are truly global, represented by similar temporal trends — atmospheric greenhouse gases, global surface temperatures, nitrogen fluxes to the coastal zone, and species extinctions. Striking is the extent and rate at which humans have modified Earth’s land surface; as just one example, humans are now the largest force in the movement of sediment — greater than ice, wind and water. The traces of humanity (e.g. petroleum wells, geotechnical boreholes, mining-exploration holes, and deep-water wells) will last millions of years. Historical deforestation and land clearing have greatly impacted soil erosion, hill slope failure and downstream sedimentation. In this talk, I will discuss how, by any measure, we have entered a new geological era (labeled the Anthropocene), unique to the history of our planet. Some of these changes have crept up on us; others have gone unrecognized until recently. Global sustainability involves facing our risks both global and local and aligning governance with stewardship.