Microelectrode arrays have great potential as analytical tools because currents an be independently measured at each electrode in the array. In principle, these currents can be monitored in order to follow in real time the binding events that occur between the members of a molecular library and a biological target. To capitalize oil this potential, the surface of the array must be selectively functionalized so that each unique member of the molecular library is associated with a unique individually addressable electrode or set of electrodes in the array. To this end, this instructional review summarizes methods for coating the arrays with porous polymers that allow for the attachment of molecules to the surface of the array, selectively conducting reactions at individual electrodes in the array, characterizing molecules that are placed on the arrays, and running the analytical experiments needed to monitor in real time binding events between molecules on the array and a biological target.