In conjunction with the rapid growth in adopting smart devices, the smart cities concept has been raised simultaneously in many modern societies. A smart grid is an essential part of any smart city as both consumers and power utility companies benefit from the features provided by the power grid. In addition to advanced features presented by smart grids, there may also be a risk when the grids are exposed to malicious acts such as security attacks performed by terrorists. Many vendors develop smart meters and at the same time, many researchers have proposed various supported security systems, however, no security measures were considered in most of those designs. This book presents a security study for smart metering systems with a prototype implementation for future works.