Abstract: A monolithic, multi-color semiconductor light emitting diode (LED) is formed with a multi-bandgap, multi-quantum well (MQW) active light emitting region which emits light at spaced-apart wavelength bands or regions ranging from UV to red. The MQW active light emitting region comprises a MQW layer stack including n quantum barriers which space apart n?1 quantum wells. Embodiments include those wherein the MQW layer stack includes quantum wells of at least two different bandgaps for emitting light of two different wavelengths, e.g., in the blue or green regions and in at least one other region, and the intensities of the emissions are adjusted to provide a preselected color of combined light emission, preferably white light.