[en] The DT, DD and DHe fusion fuel cycles are compared on the basis of safety and economics. The designs for the comparison employ HT-9 structure and helium coolant; liquid lithium is used as the tritium breeder for the DT fuel cycle. The reactors are pulsed superconducting tokamaks, producing 4000 MW thermal power. The DT and DD designs are developed utilizing a plasma beta of 5%, 10% and 20%, assuming first stability scaling laws; a single value of 10% for beta is used for the DHe design. Modest extrapolations of current day technology are employed, providing a reference point for the relative ranking of the fuel cycles. Technological advances and improved understanding of the physics involved may alter the relative positions from what has been determined here. 92 figs., 59 tabs