This book is about as accessible as you can get with Heidegger. Gelven not only manages to put across BT's basic concepts in a way which is understandable and jargon-free (though by the end of it the jargon starts to make sense), but also weaves them together into a reasonably coherent presentation of the work in general. So not only does each section make sense taken alone, but he also lets you see how they fit into the general picture. This is probably a better intro to BT than Dreyfus' book, which is in fact a re-hashed set of lecture notes. Contrary to one of the other reviewers, I would recommend reading this commentary before reading Heidegger's actual text. If there is some genius out there who can make sense of Being and Time without being fully versed in the phenomenological tradition, and can therefore makse sense of BT without any help, then I don't think Gelven's book is much help. But for mere mortals this book is indispensable. As for other commentaries, Mulhall's is a bit less clear and more heavy going, but a good follow-up to Gelven. Inwood's is maybe a bit too concise, but worth reading too. For the record, I'm a postgraduate researcher drawing quite heavily on Heidegger's philosophy, so have ended up spending a fair amount of time on this stuff. Life would have been much more difficult without Gelven.
