A concept is presented for a fusion neutron source based tritium production reactor called the Tokamak Tritium Production Reactor (TTPR), which could meet the U.S. needs for replenishment of weapons tritium during the first half of the next century. The TTPR concept is based on physics and technology that either exists or is being developed and will be tested under integrated, prototypical conditions in the International Thermonuclear Experimental Reactor (ITER). The TTPR can provide 2 kg/yr tritium for weapons replenishment operating at a fusion power level of 500 to 1000 MW and at a plant factor of 10 to 25%. No structural component should need to be replaced because of radiation damage during the 40-yr lifetime of the TTPR, and it should be possible to dispose of the TTPR on decommissioning as low-level waste that qualifies for shallow land burial.