Inertial confinement fusion requires the generation and focusing of several megajoules of energy at > 100 TW power and > 100 TW·cm−2 power density onto a target for approximately 10 ns. Lasers and particle beam drivers have been developed for this purpose. Lightion beams offer the potential for a cost-effective, efficient and versatile driver with excellent energy deposition and no significant preheat. The research and development to date has emphasized technology development of the driver. Advances in pulsed power technology, magnetically insulated power flow, intense ion beam generation, focusing and transport, and ion beam deposition have led to the Particle Beam Fusion Accelerator II at Sandia National Laboratories which will begin operation in January 1986. This accelerator has the potential for achieving ignition of thermonuclear fuel in the laboratory.