This paper presents a line of research in reversible computing for concurrent systems. This line of research started in 2004 with the definition of the first reversible extensions for concurrent process calculi such as CCS, and is currently heading to the production of practical reversible debuggers for concurrent languages such as Erlang. Main questions that had to be answered during the research include the following. Which is the correct notion of reversibility for concurrent systems? Which history information needs to be stored? How to control the basic reversibility mechanism? How to exploit reversibility for debugging? How to apply reversible debugging to real languages?