Ferroelectricity has been time-honored subject in terms of various electronic, electro-mechanical, and optical functions. Developing organic ferroelectrics with advantages of light-weight, flexible, low-cost, and environmentally benign characteristics is surely in demand, yet needs elaborate chemical designs of objective functions. This review describes modern chemical approach to improved dielectric, ferroelectric and/or thermal properties, based on the charge-transfer complexes and hydrogen-bonded compounds.