We have successfully synthesized a range of inorganic nanosheets by chemically exfoliating layered compounds.As-obtained nanosheets can be categorized as a unique class of nanoscale materials, which are characterized by their extremely thin layers of 0.5-3 nm in thickness and very high 2D anisotropy. These colloidal nanosheets can be assembled into highly organized nanostructures such as multilayers and superlattice systems by means of solutionbased processes. This approach allows us to develop the advanced functionalities such as high dielectric performance even at a nanoscale thickness, gigantic magneto-optical property in response to UV-to-visible light, and seed layer function for oriented growth of various crystal films. These materials and techniques show great promise for applications in next-generation electronics.