The essence of autonomy is one’s freedom to make a decision or self-government in its general understanding. In the context of technical systems, one can refer to a system’s ability to generate decision alternatives and select a decision on its own as a result of decision-making algorithms or other mechanisms. The field of robotics and intelligent systems has grown explosively over the last decade, and Unmanned Systems (UMS) is being fielded with increasing frequency in different domains including logistics, automotive, industrial cleaning, military, and many more applications. However, as a consequence of this rapid advancement, a lack of agreed-upon standards, definitions, and evaluation procedures for UMSs exist. While a wide range of both autonomous and semi-autonomous UMSs are available for use, no measure yet exists to measure what the impact increased or decreased autonomy has on UMS performance. In other words, not always, it is obvious how the degree of autonomy correlates to the performance, safety, and usability of a given system. The following chapters provide an overview of the autonomous systems from different domains (application area) and particular technological specifics: