We report on the observation of spin wave quantization in tangentially magnetized Ni80Fe20 disks by means of Brillouin light scattering spectroscopy. For a large wave vector interval, several discrete, dispersionless modes with a frequency splitting up to 2.5 GHz were observed. The modes are identified as being magnetostatic surface spin wave modes quantized by their lateral confinement in the disk. For the lowest modes, dynamic magnetic dipolar coupling between the disks is found for a disk spacing of 0.1 μm. © 2000 American Institute of Physics.