Entanglement is one of the fundamental features of quantum information science. Though bipartite entanglement has been analyzed thoroughly in theory and shown to be an important resource in quantum computation and communication protocols, the theory of entanglement shared between more than two parties, which is called multipartite entanglement, is still not complete. This book contains Dr. Wei Cui's research regarding the classification of multipartite entanglement and the transformation property between different multipartite states by local operators and classical communications (LOCC), which are two fundamental questions in the theory of multipartite entanglement.