The main topics discussed in this book are the formation of the macromolecular condensed state from isolated long chain macromolecules in dilute solution, the salient physical behavior of the polymeric amorphous state, the liquid crystalline state of rigid chain polymers, the crystallization process and the single chain condensed state, all based on experimental results. The role of intersegmental cohesion and the difference between the single chain condensed state and the interpenetrated multichain condensed state are emphasized. In addition, the book introduces and discusses some new physical concepts, such as dynamic contact concentration, the looped chain, cohesional entanglement, the GOLR state (the global chain is highly oriented while the segmental orientation is completely random) and solidification-induced band texture.