Due to the fast growing field of nanotechnology in the 21st century, production of the materials able to interact with light for particular optical purposes is under the focus of many research communities all around the world. Plasmonic nanomaterials are among those structures which have been spotlighted due to their exotic properties originating from their plasmon resonance and their great potential for being the host of applications ranging from optics to energy. In this chapter, we overview different aspects of plasmonic nanocomposites, from fundamental ones (i.e., absorption and scattering) to fabrication and tailored parameters. In addition, the new concept of plasmonic nanocomposites with specular reflection is also presented and discussed along with its diverse applications in the field of energy-saving solar materials. The prospective outlook introduces a new class of molecular plasmonic composites operating based on the oscillating dipole of photoswitchable molecules.