<div> Small molecules and conjugated polymers are the two main types of organic materials used for optoelectronic devices. Organic materials are attractive due to their low cost, the ability to tailor their properties and the ability to integrate them with inorganic semiconductors. The editor and contributors look at the materials used for organic optoelectronics and nonlinear optics, their properties, and methods of their characterization illustrated by physical studies. They then move on to discuss the applications of optoelectronic and nonlinear optical organic materials in devices and include chapters on organic solar cells, electronic memory devices, electronic chemical sensors, electro-optic devices, and other applications.</div>