Smart-irrigation systems are a hot topic in irrigation management. Satellite imaging, sensors and controls, communication technologies and irrigation decision models are readily available. The price of the required technology is being reduced year after year, and its implementation in agriculture gives real-time information that allows for more accurate management of water resources. Even so, the adaptation of existing technologies to particular situations that the irrigation management is facing in different agro-environmental contexts is needed. This Special Issue addresses the application of different smart-irrigation technologies in four different research areas: (1) remote sensing-based estimates of crop evapotranspiration, (2) Information and Communication Technologies (ICTs) for smart-irrigation, (3) precision irrigation models and controls, and (4) the price of natural resources. The nine papers presented in this special issue cover a wide range of practical applications, and this editorial summarizes each of them.