Microspheres are polymeric micron range particles with sizes from 1 to 1000 µm. These microspheres are used for drug delivery, wherein the drug can be encapsulated or entrapped form. Based on the polymeric composition of microspheres, they can be classified into two types: natural and synthetic. They are mainly used for targeted drug delivery of anti-cancer agents, ophthalmic agents and can be used for diagnosis purposes. They can also be used in imaging technology, used in the preparation of microsponges and magnetic microspheres also. The book consists of the development and characterization of candesartan microspheres.