Predictions have been made of how total withdrawal of supporting electrolyte affects the steady-state limiting current at a rotating disk electrode. Incorporating transport by diffusion, migration, and convection, the treatment is restricted to a three-ion system under the assumption that all the ions share the same diffusivity. The results predict qualitative, but not quantitative, agreement with similar studies relating to steady-state voltammetry at a hemispherical microelectrode. The experimental findings of Gao and White are discussed in the light of the new treatment.