Femtocells extend the cellular network coverage and provide high speed data service inside homes and enterprises for mobiles supporting existing cellular radio communication techniques. They also provide additional system capacity by offloading macro network traffic. This article reviews the characteristics of cdma2000-based femtocell systems. It discusses design and deployment aspects such as carrier allocation, access control, efficient support for femtocell discovery by idle mobiles, and active call hand-in from macrocell to femtocell. The evolution of the cdma2000 standard for optimizing performance and enriching user experience with femtocells is also discussed.