This book deals with functionalization of calix[4]arene molecules at lower rim and its application in various fields such as liquid crystals, bio-activity and sensor. Calixarenes, with their unique three-dimensional surface, are one of the best known host molecules along with cyclodextrins, cucurbiturils, cryptands, and crown ethers. By their availability and easy functionalization at either the upper or lower rim of the molecular skeleton among potential building blocks, calixarenes have become important receptors in synthesis and applications as supramolecular platforms for molecular recognition, sensing and self-assembly, catalysis, nanotechnology and drug discovery.