Since last few decades, nematic liquid crystals have shown huge impact on display applications. Doping nematic liquid crystal with small amount of host can significantly alter the physical properties such as electro-optic response time, relaxation time, and viscoeleatic properties of host nematic. This field of doping is currently an important and exciting area of research. However, through doping with guest molecule it is quiet convenient to have control over physical properties of host. This book discusses explicitly about the doping of nematic host with azobenzene molecules, carbon nanotubes, confinement of nematic in restricted geometry such as aerosil particles, salt effects on chromonic nematic liquid crystals and nematic liquid crystal gel formation. Present work explicitly demonstrates the potential for creating photonic devices in various applications.