In recent years, precision agriculture (PA) researchers have found that the use of unmanned aerial vehicles (UAV) could significantly improve agricultural sciences research. Their motivation was conceived by its availability, simple assemblage and maintenance, as well as its low cost compared with traditional tools (e.g. Satellites, manned aircrafts). For this reason, significant efforts are being made to use a new generation of mini UAV applied to Remote Sensing (RS). This book addresses the development of tools dedicated to RS missions over agricultural fields, in particular, an aerial mission planner. Finally, a survey of experiments carried with a type of mini UAV denoted as quad-rotors in real agricultural scenarios is also provided.