The interfacial properties of gold nanocrystals deposited electrochemically onto glassy carbon substrates are characterized. Electrochemical interrogations as well as microscopy have been utilized to examine systematically the influences of deposition solution concentration and overpotential. The results of these studies indicate that the overall surface area of gold as well as nanocrystal size, density, and surface texture, can be controlled by variation of deposition conditions. From this work, arrays of gold particles which are suitable sites for future chemical modification can be produced on glassy carbon surfaces. These interfaces will be utilized for the fabrication of analytical electrodes with segregated sites exhibiting selectivity and facile electron transfer.