This chapter focuses on the use of radio signals for human body motion recognition and sensing purposes. The technology relies on the use of the same electromagnetic (EM) fields adopted for wireless transmission. Radio signals adopted for recognition can be either narrowband or wideband, in licensed or unlicensed frequency bands, with carrier frequencies ranging from MHz to GHz, and above. In order to support human sensing and imaging functions, three key distinctive technological features are incorporated; these are summarized in the following: sensorless interaction and anonymous tracking; ubiquitous monitoring; and scalable channel quality information (CQI) analytics. Wireless human tracking via RF devices encompasses different research areas such as signal processing, computer vision, communication networks, and human–machine interfaces. The chapter reports the most recent research results for selected relevant applications. It presents a specific case study that focuses on device-free localization (DF-L) and fall detection inside a human–robot-shared industrial workplace.