In this book, we have tried to present some recent development in high-temperature multifunctional materials with their prospective application in smart and multifunctional devices. We have introduced the various concepts which realize the multifunctional concept via magnetoelectric coupling with the classification of different types of multifunctional materials including multiferroic polymer nanocomposite. Besides this, an attempt has been made to restrict the multifunctional materials which have only the specific criteria that have high k-value beyond room temperature with high magnetoelectric coupling constant that will have potential application in various fields including 4 state memory devices, magnetic field sensor, transducer, etc. with illustrative examples.