This has some interesting information and provides a quick over-view of a number of different systems but the issue is that some of them are based on out-dated versions which is completely useless for someone who is interested in a particular system and would like to look into it further. Case in point - Castles & Crusades. It says it is based on the 2004 edition which has not been available for years so if someone was to pick up the currently available version it will be completely different and virtually unrecognizable to the version that is reviewed. Basic Fantasy Role-Play as well, is based on the 2nd edition which has been updated to 3rd edition years ago. It may have some use if you are interested in the history of these games but as it is marketed as a 'Handbook' I don't feel that it offers much information on the current state of the OSR due to the out-of-date information on some of the systems. If you are looking for current information on a certain game system or are wanting to research new systems to try the information will be hit and miss depending on the system. I feel this would be much more useful if information about the currently available edition(s) was included.