A FEMTOCELL is a small, low-power cellular base station, typically designed for use in a home or small business. It connects to the service provider’s network via broadband (such as DSL or cable). Femtocell technology is expected to improve both coverage and capacity, especially indoors. Providers of cellular services are increasingly implementing this technology in their networks. It is a new development in networking technology which improves coverage, voice quality and battery life. Many operators have already launched femtocell service, including Vodafone, SFR, AT&T, Sprint Nextel, Verizon and Mobile TeleSystems. So it will be interesting and necessary to know about this new technology. This paper gives an overview of the new femtocell technology, the advantages it provides by incorporating it into the existing wireless networks, difference between open and closed access Femtocells and the issues that prevent the mass deployment of Femtocells.