Semiconductor lasers are aged to identify weak or flawed devices, resulting in improved reliability of the remaining devices. The lasers can be aged using a high-power optical burn-in that includes providing a high drive current to the lasers for a period of time, and maintaining the ambient temperature of the lasers at a low temperature. After the high-power optical burn-in, the output of the lasers can be measured to determine if the lasers are operating within specifications. Those that are not can be discarded, while those that are can be further aged using a high-temperature thermal burn-in that includes providing a drive current to the lasers while maintaining the ambient temperature of the lasers at a high-temperature.