Now looking back on a proud 30-year history, deep geologic waste isolation projects have proven to be environmentally friendly and economically advantageous neighbors. Examples range from the first repository for industrial chemotoxic waste in a German potash mine to an excavated facility dedicated exclusively to the permanent isolation of radiotoxic defense waste in New Mexico. Long material cycles in the earth’s crust make the disposal of ecotoxic materials into thick impermeable rocks in geologically stable areas the preferred choice in many countries. Actual operating and monitoring experience consistently adds to our confidence in satisfactory long-term repository performance. Geological theory and practice put the lie to the old assertion that the nuclear and hazardous waste issues are not susceptible to environmentally compatible solutions. That realization is key to the growing support, which geologic waste isolation projects enjoy among prospective and actual neighbors.