The book summarizes Ting Lei’s PhD study on a series of novel conjugated polymers for field-effect transistors (FETs). Studies contain many aspects of polymer FETs, including backbone design, side-chain engineering, property study, conformation effects and device fabrication. The research results have previously scattered in many important journals and conferences worldwide. The book is likely to be of interest to university researchers, engineers and graduate students in materials sciences and chemistry who wish to learn some principles, strategy, and applications of polymer FETs.