Book excerpt: Organic materials are attractive due to their low cost, the possibility of their deposition from solution onto large-area substrates, and the ability to tailor their properties. In the second edition of Handbook of Organic Materials for Electronic and Photonic Devices experts provide an overview of the materials, mechanisms, characterization techniques, structure-property relationships and most promising applications of organic materials. The second edition includes new content on emerging organic materials, expanded content on the basic physics behind electronic properties, and new chapters on organic photonics. Advances in organic materials design, fabrication, and processing that enabled charge unprecedented carrier mobilities and power conversion efficiencies have made an update to the first edition necessary. The new edition also reflects the latest advances in understanding of underlying physics that enabled novel material design and improved organic device design. Provides a comprehensive overview of the materials, mechanisms, characterization techniques and structure property relationships of organic materials Reviews key applications including organic solar cells, light-emitting electrochemical cells, sensors, bioelectronics, memory devices and lasers New content to reflect latest advances in understanding of underlying physics to enable material design and device fabrication