 Climate change has led to increased awareness of energy efficiency which has resulted in new trends in electricity markets such as the obsolescence of the traditional electricity model and the gradual conversion of consumers to prosumer profiles. To address this shift, the introduction of multiple distributed generation and storage resources with a strong involvement of renewable energies requires advanced metering or smart metering systems which must be able to manage and control these distributed resources. These systems have been developed using a variety of technologies and standards each with its own set of features. This paper reviews the key elements of a smart metering system including the technologies and standards used and provides an overview of the deployment of smart metering systems around the world. This article was authored by Noelia Uribe Perez, Luis Hernandez, David de la Vega and others.