Abstract: AC and/or DC testing of an optoelectronic device at the wafer level. In one example embodiment, a method of testing one or more devices at a wafer level includes generating a test signal; supplying the test signal to a single device on a wafer; providing an output of the single device to each of a plurality of devices on the wafer by way of a common electrical connection between the single device and the plurality of devices; providing an output of each of the plurality of devices to a corresponding return connection by way of electrical connections between the plurality of devices and the plurality of return connections; and receiving return currents from each of the return connections.