Our modern society depends to a great extent on the functionality and efficiency of all the mechanical machinery that we see around us and use every day. All these machines involve numerous tribological contacts. A contact between two surfaces that are in motion relative to each other will result in friction and wear.A constant trend towards more compact mechanical systems with higher power densities requires them to operate in increasingly severe conditions, which heavily influence tribological contacts. They, in turn, affect machine efficiency and impose a limit on machine reliability and service life. Present tribological systems are passive, i.e. their performance cannot be tuned on-line. The purpose of tribotronics is to control so-called loss outputs in a tribo-mechanical system: friction, wear, vibration, etc. Such a system includes sensors, a control unit and actuators. A tribotronic system is thus autonomous and self-adjusting. This allows for on-line tuning of the tribological components for the best performance. This paper illustrates how tribotronic systems can facilitate e-maintenance and thus provide foundation for the best maintenance decisions.