Laser-induced intermixing of a buried InGaAs/InGaAsP multiquantum well structure using a CW Nd : YAG laser, operating at a wavelength of 1064 nm, has been demonstrated. The process does not involve transient melting of the semiconductor, but relies on preferential absorption by the active region producing sufficient heat to cause intermixing between the wells and barriers. Photoluminescence measurements at 77 K indicate that bandgap shifts as large as 123meV are obtainable using moderate laser beam power densities and periods of irradiation.