A III-nitride based quantum dot (QD) laser is formed of InGaN/GaN quantum dots and capable emitting at a single wavelength within the visible region, including the violet wavelength region (400-440 nm), the blue wavelength region (440-490 nm), the green wavelength region (490-570 nm), the yellow wavelength region (570-590 nm), the orange wavelength region (590-620 nm), and the red wavelength region (620-700 nm), with varying composition as described.