If you are looking for a gentle introduction to Hinduism, I cannot stress enough that you should look at Huyler's "Elements of Hindu Devotion" before you read this. This is a fine book, but I just can't say it's a good introduction.
I disagree with the reviewers who say that Klostermeier assumes no prior familiarity with Hinduism. He assumes no prior significant study, but he just doesn't explain things at an introductory level. The general problem is that the information is not organized the way it ought to be in an introductory book. To be frank, it's almost as though the author assumes you already know pretty much what he's saying. In fact, it's not too hard to deal with if you already know, but if you don't, a lot of the text will be opaque.
For instance, you'd better realize that Nyaya, Vaisesika, Samkhya, Yoga, Purva Mimamsa and Vedanta are schools of philosophy, and that advaita, visistadvaita, and dvaita are schools of Vedanta before you pick up the book. Now to be fair, you can figure this out if you read the book very closely, as though it were a puzzle to be decoded. For instance, we are told that Sankara is the great advaita theologian on page 413; that's the 16th mention of Sankara, and the 6th of advaita. It's certainly basic information, but it would be pretty confusing to read all those references to Sankara and advaita if you didn't know what they are.
That's an example; just about every topic in the book suffers from the same problem.
However, if you've read two or three books on Hinduism before, this is not a bad book at all. It actually has a lot of detail. The most interesting aspect, perhaps the main reason it's famous, is that most people believe the author succeeds in presenting Hinduism on its own terms, not in terms of Western religion or "orientalist" scholarship.
Let me describe the contents.
It starts with a nice but very brief introduction to Western perspectives on Hinduism. Next, an extremely brief introduction to the history of Hinduism, though you'd better know already about the Aryan invasion theory and the fact that it's become quite controversial. If you do, then Klostermeier's information is very interesting. Then he considers the issues of "orthodoxy" and "heresy" within Hinduism, essentially a consideration of the boundaries of Hinduism, and disagreements about them. Next he covers the scriptures, a very complex topic and this is one of the better explanations of it that I've read. He also looks at the idea of "revelation" and "sacred word," though I'd say too briefly. The next chapter, on the two great epics and the Puranas is excellent; the chapter on the Bhagavad-Gita (read it!) is ok. The cosmology chapter is ok. The next chapter introduces the Hindu deities from the Vedas to the present time. In some aspects, this is a very good chapter; but if you want to know how the deities are/were worshiped, there is nothing here. It is all mythology and theology.
Next, a couple chapters on "karmamurga" (the path of works) and ethics. Then a very brief introduction to the samskaras (initiation, marriage, cremation). Next, several chapters give a pretty good historical introduction to Jnanamarga (the path of knowledge) and the Upanishads: atman, Brahman, karma, moksa (liberation). Then, an introduction to bhaktimarga (the path of devotion), far too brief and colorless, but its history is well told. That leads to pretty good chapters on Visnu, Shiva, and Devi, followed by an interesting chapter on the great gods of the Tamil Nadu region.
Then he turns even more toward theology, looking at Hindu constructions of sacred time and space. This chapter is both interesting and introductory, though the subject deserves better coverage. Next is the caste system, which he describes without indignation. Next, he looks at the varieties of holy men and women, briefly but informatively outlining the major modern groups. He has a fine introduction to the situations of women in Hinduism, which is the first time he really shows any criticism in the book. Now there's several chapters on the schools of philosophy, which, if read closely, are very good.
Next, a fine chapter on modern Hindu reforms and reformers, with emphasis on figures that have impacted India rather than ones that have impressed the West, including an interesting but very brief section on Indian secularism; and another fine historical chapter on Gandhi (that could in many people's opinion be more critical). The last chapter, which is on Hindu nationalism, is one of the best in the book.
In short, this book is full of good, basic information and plenty of interesting details, examined in pretty good depth for an introductory book. However, it is so poorly explained and organized, that I recommend reading a few books on Hinduism before coming to this one.
Further, you will get no sense of the power, wisdom or beauty of Hinduism from this book: it will overwhelm you with the all the varieties of everything first. If you don't love or admire Hinduism when you start this book, you'll feel no more warmly when you finish. I can't think of anything in the book that really impressed me as interesting, beautiful or wise, which is a big failure for a supposedly introductory book.
A minor criticism is that the 22 B&W photographs are not particularly revealing, but fortunately we live in the age of the google image search, so you can overcome that easily if you care to. Also, there are so many typos that the editor, if there was one, has to be criticized.
A minor point in the books favor, although this is important to me, is that it is well made. The binding is excellent, the paper is good, the margins are large enough for making simple notes but not too wide. The bibliography is excellent, particularly for scholarly works by Hindus. There's a very thorough glossary, practically a mini-dictionary, and the text consistently gives both Sanskrit words and their English translations.
Let me alert you to some other excellent introductions. After Huyler's book I mentioned above, I would strongly recommend "The Camphor Flame," which is (I think) by C. J. Fuller, which is the best book on Hinduism that I've ever read, although Huyler does a better job of presenting Hinduism at a basic level. It really is the best "2nd book" on Hinduism, IMO. After that you have options, with this being among the pretty good ones. (Yes, I'd say this is a very good 3rd book or so.) Of course, there are a lot of introductions out there, and some of them are surely as good as these, but these are the ones that I've read and can happily recommend.
This book is a very thorough description of many aspects of Hinduism. The book is written for a Western audience, so the author assumes no prior familiarity with Hinduism on the part of the reader. The book is organized into four sections: development and essence of Hinduism, the three Hindu paths to liberation, the structural supports of Hinduism, and the meeting of East and West in modern India. Each section contains a number of chapters addressing specific topics that fall within the general topic of the section. The end material, which comprises over 200 pages, contains a chronology, endnotes, a glossary, a bibliography, and the index.
The style of writing is extremely dense and detailed, yet the vocabulary and presentation are still quite accessible to non-Indian audiences. The extensive footnoting, use of primary and secondary source material, and lengthy quotations make this a remarkable work of scholarship. The text itself is more like an encyclopedia in nature; the chapters are independent articles in themselves, so there is little cohesion from one chapter to the next. Some of the chapters are quite interesting and illuminating- -others cover material that is of more marginal interest. I almost put the book down after struggling through chapter 1, which provides a rather detailed history of Western scholarship on Hinduism, and might have made a better appendix than an introduction. But fortunately, I kept slogging through the material, and learned quite a bit about the core Hindu beliefs from subsequent chapters. The book would make a good textbook for classes on comparative religion or South Asian cultures. It may also provide some answers for independent readers with a burning curiosity about Hinduism.