With the required miniaturization, the materials combining different functionalities have become interesting. In this topic, a variety of advanced polymer nanocomposites will be introduced. Methodologies to prepare nanocomposites and their effects on the produced nanocomposites will be introduced. Unique properties including mechanical, electrical, magnetoresistance etc. and the applications for environmental remediation, energy storage/saving and electronic devices (Sensors and Electrochromic Display Windows) will be presented.