In this report we presents an overview of the Capacity of Code Division Multiple Access (CDMA) Systems. In the past, it has been shown that CDMA is the most suitable multiple access transmission technology for Mobile Communications and all the 3rd Generation Mobile Communication Standards suggest CDMA for the Air-Interface. The head reason for the powerty of this technology is the large increase in capacity offered by CDMA systems when compared to other analog or digital transmission systems. This report summarizes some of the early work done on the capacity calculations of CDMA systems.