General formalisms have been developed, based on Robbins’ theorem, to describe overlap phenomena for two-dimensional nucleation and growth on electrodes of finite extent. Earlier theories of Smith and Fletcher and Bosco for finite geometries are generalized to time-dependent nucleation. Using the present formalism, coverage and current transients were computed for circular electrodes. Analytic expressions are presented for the sphere and half-sphere problems. Earlier work of Sridharan and de Levie and Harrington is also discussed.