Efforts worldwide to find viable thermoelectrics (TE) are intensifying . We have achieved selective scattering of phonons and thereby critical enhancement of TE properties through nanostructuring: both a) mechanical and b) bottom-up methods. For example, previously, quick, inexpensive, bottom-up wet processes were found to fabricate nanosheets of telluride thermoelectric materials leading to enhanced ZT . We have also recently discovered a bottom-up nanostructuring method leading to a 100% enhancement (i.e. ZT≈1.6) in“empty” rare earth-free skutterudites , and details and possibilities to apply to other materials will be presented. This work is supported by CREST, JST.  <I>Thermoelectric Nanomaterials</I>, ed. K. Koumoto and T. Mori, (Springer, Heidelberg, 2013).  C. Nethravathi et al., J. Mat. Chem. A, 2, 985 (2014).  A. U. Khan et al., submitted.