This chapter presents feedback cooling of all three rotational (librational) motions of a nearly spherical nanoparticle. In previous studies, cooling librational motion has only been realized in highly anisotropic particles. We demonstrate that even nearly spherical nanoparticles confined in a one-dimensional optical lattice can exhibit three-dimensional angular confinement due to optical potential anisotropy. Moreover, using an electrical cold-damping technique, we cool all three librational degrees of freedom to effective temperatures below \(30\,\textrm{mK}\) . These results open a pathway to precision torque sensing and to exploring the quantum behavior of rotational motion.