Relay technologies have the potential to offer extended cell coverage and improved capacity over the Next Generation Wireless Broadband Radio Access Networks. Standards development organizations are considering how to incorporate relay technologies into new standards. This article provides an overview of the relay-based technology concepts for two of the most promising next generation wireless broadband networks: WiMAX and LTE, focusing on some of the most pertinent aspects. In particular, the various potential relaying scenarios are described, while the integration and adaptation of the Multi-hop Relay in the framework of WiMAX and LTE networks is analyzed. Some consideration of the issues in designing such systems is also given, which highlights when different features within the standard are most appropriate. As these systems are very new, many open issues remain to be resolved.