This chapter summarizes the key achievements of the thesis and discusses future directions for research in levitated nanoparticles. The first achievement is the realization of six-degree-of-freedom feedback cooling of an electrically neutral nanoparticle trapped in a one-dimensional optical lattice. Notably, motion along the optical lattice axis is cooled to the quantum ground state. The second achievement is the direct measurement of the particle’s velocity distribution using time-of-flight. These achievements lay the groundwork for the potential observation of macroscopic quantum interference and may also open pathways to applications in precision sensing, including accelerometry and torque detection. The remaining challenges, such as decoherence due to photon recoil and blackbody radiation are identified, and possible solutions such as alternative trapping systems, are discussed as avenues for future system designs.