We survey recently-reported, analytical solutions for the study of simple and complicated charge transfer reactions by means of any voltammetric technique with electrodes of very different geometries under conditions where the mass transfer takes place only by diffusion, that is, in fully-supported media where migration can be neglected. Under transient conditions, expressions are reported for one-electron and multi-electron reversible transfers, electrode reactions coupled to homogeneous chemical equilibria and the first-order catalytic mechanisms with electrodes of any geometry. The steady-state voltammetric response of the above systems will also be considered at submicro- and nanoelectrodes of very different shapes and arrays. Also, a universal approach to the steady-state voltammetry of sluggish electron transfer processes is presented. Finally, solutions for ion transfer processes across (sub)micrometric liquid/liquid interfaces is discussed. (C) 2015 Elsevier B.V. All rights reserved.