A wireless sensor network (WSN) is a wireless network consisting of large populations of spatially distributed sensor nodes to cooperatively monitor physical or environmental conditions. Wireless sensor networks have many useful applications such as hostile environment surveillance, industrial process monitoring, environment and habitat monitoring, healthcare applications, home automation, and traffic control. The last few years have witnessed the development of many innovative solutions for wireless sensor networks that are maturing to the level of commercialization and standardization. More recently, latest research result shows that the rapidly development of localization technology can be combined with WSN to enhance its scalability, robustness and mobility. The according improvements on existing applications will further facilitate our daily life. Given the many application scenarios across the multiple disciplines, there is a clear need for a broad, up-to-date and cogent treatment of wireless sensor network and related positioning services.