The theory of cyclic voltammetry at linear gold microelectrodes of thicknesses less than 1 μm has been examined for electrode processes where the electron-transfer step is rate determining. Digital simulation (expanding-grid method) is used with cylindrical diffusion in all theoretical calculations. Results of the theory in the limit of the reversible response are in agreement with previously published theories and with experimental data obtained in this work. Unlike microdisk electrodes, departures from the steady-state sigmoidal shaped curves are expected and observed experimentally, provided considerable attention is given to electrode design. The very thin electrodes achieve the desirable goal of having almost purely cylindrical diffusion and consequently may be used in high-resistance solutions and for measurements of very fast rates of electron transfer. The large total area, provided by the dimension of length, means that measured currents can be sufficiently large so that transient voltammetric methods may be implemented with conventional instrumentation. The combined use of computer modeling of the theory and comparison of experimental data obtained from microdisk electrodes, linear arrays of microdisk electrodes, linear microelectrodes, and microring electrodes has enabled microelectrodes to be systematically classified. The linear electrodes with submicrometer width are a subset of microelectrodes ranging from the two extremes, the microdisk and the microring electrodes.