High-power CW operation of transverse-mode stabilised InGaAlP laser diodes has been achieved by using a selectively-buried-ridge waveguide structure with a very thin (150 angstrom) active layer. A strained In0.62Ga0.38P active layer was adopted to obtain a sufficient bandgap difference between the active and cladding layers. A maximum light output of 106 mW was obtained from the laser with antireflection and high-reflection coatings.