Machine tools for small work pieces are characterized by an extensive disproportion between workspace and cross section. This is mainly caused by limitations in the miniaturization of drives and guidance elements. Due to their high specific workloads and relatively small spatial requirements, Shape-Memory-Alloys (SMA) possess an outstanding potential to serve as miniaturized positioning devices in small machines. However, a disadvantage of known actuator configurations, such as SMA wire working against a mechanical spring, is that energy is steadily consumed to hold defined positions. In this paper we present a novel SMA actuator design, which, due to an antagonistic arrangement of two SMA elements does only require a minimum amount of energy whilst holding position. The SMA actuators were designed regarding material, geometrical parameters, applied load, and control aspects. Furthermore, closed loop control concepts for positioning applications are implemented. These not only cover approaches using sensors, but also sensorless concepts which utilize the distinctive length - resistance - correlation of SMAs for position controlling. Furthermore, an actuator demonstrator has been used to demonstrate the designs capabilities to serve as miniaturized positioning device in small machines. In addition the novel design concept of the SMA actuator will be compared with commonly used approaches.