While I teach a lot of Open Water courses my favorite course to teach is the PADI Rescue Diver. Here at Davy Jones Locker we typically spread over 3 days with theory, confined water training followed by a session in the sea. The course is often taught in conjunction with the Emergency First Responder (primary and secondary assistance course). It runs through possible scenarios of what may go wrong before and during a dive and will teach you how to recognise them and respond to them safely. The fun part for me is being able to relate to students real stories of problems that have occurred but exaggerating them to test how the rescue students cope in different situations and getting them to start thinking safely by going over what we did and how we would do it differently next time so that we all improve our diving skills, and my teaching skills as there is always something I can do better.
It will be highly unlikely that you will ever have to use these rescue skills, but wether you are honing your dive skills as a recreational diver or taking it as a step towards the PADI Divemaster programme it will teach you to be a more safer and aware diver whilst giving you the training and confidence to deal with an emergency.