A review is given of progress in ion source performance at the cw test stand. Data is presented both for pure and cesiated source performance. For uncesiated operation we show how the performance depends on cathode area by changing both filament number and diameter. We have proved that this is due to the collection of ions from the plasma by the cathode structure. Through the use of cesium in the ion source the H−and D−current is enhanced by about a factor of two. An accelerator perveance limit was identified which prevented all the current available from the source being transported, but this was overcome by a new accelerator design allowing very high currents, 86 mA of H−and 37.3 mA of D−, to be extracted from a 16 mm diameter aperture.