Case-based reasoning (CBR) is a sub-field of Artificial Intelligence that deals with experience-based problem solving. CBR has its roots in different disciplines such as cognitive science, machine learning, and knowledge-based systems. Today, it is a well established research field of its own, which produced a rich variety of specific methods, as well as applications implementing those methods for particular tasks and domains. This paper gives a compact overview of CBR in general and further discusses recent advancements in selected topics.