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Positive ions can make efficient neutral beams when direct energy conversion is incorporated at energies up to 150 keV for D exp 0 , 225 keV for T exp 0 and 300 keV for exp 3 He exp 0 . Above these energies the efficiency is low (<50%) and falling rapidly, requiring other means for making neutral beams such as negative ions. The virtues of exp 3 He exp 0 beams as a heater are discussed. The role of direct conversion is discussed and the various conversion concepts and the experimental data base are reviewed. The development problems facing direct conversion are: space charge handling, secondary and primary electron suppression, and the fractional energy ions. The next step in the development of efficient neutral beams based on positive ions is argued to be a developmental beam which integrates an advanced ion source with a neutralizer, cryopump, direct converter, heat removal system, and power conditioning system. (ERA citation 03:022623)