e+ e- Factory Developments
The impressive performance of current (KEKB) and recent (PEP-II) B-Factory colliders has increased interest in developing even higher luminosity B-factories. Two new designs are being developed (SuperKEKB and SuperB). Both designs plan to deliver a luminosity in the range of 1 x 10{sup 36} cm{sup -2}s{sup -1}, nearly 100 times the present B-factory level. Achieving this high luminosity requires high-current beams and short bunch lengths and/or a new way of colliding the beams. The SuperB design employs a crabbed magnetic waist with a large crossing angle and the SuperKEKB design is looking at crab cavities with high-current beams and/or a travelling focus. I describe the designs being studied to achieve the high luminosity needed for the next generation of B-Factories.