http://www.amazon.com/FCO-Fundamental-Paul-Van-Sterren/dp/1906454132 looks good to me, although I don't own it.
Book On Ideas Behind Openings

Mastering the Chess Openings by IM John Watson (Gambit Publishing). He also has video lectures over at the Internet Chess Club. A very respected teacher. It's only $19.77 at Amazon.com for Volume 1 (1.e4), 334 pages. I have over 60 chess books and Watson's works are current as regards to opening theory (the ideas behind the moves) and perhaps the best collection of books for covering most of the main openings with a good amount of depth. I own the first three volumes.
Vol.1 (1.e4), Vol.2 (1.d4), Vol.3 (1.c4).
http://www.amazon.com/Mastering-Chess-Openings-Unlocking-Mysteries/dp/1904600603/ref=sr_1_1?ie=UTF8&qid=1299988968&sr=8-1
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EDIT
Volume One does not cover the Petroff Defense, but FCO does, however, Watson's books do not read like an Encyclopedia of Chess Openings, i.e., M.C.O., but start with ideas and strategies behind openings, followed by highly detailed explanations of fundamentals, structures, etc.
The reviews at Amazon are extremely good for FCO, especially for the beginning to intermediate player - me. Like I need another chess book! Arg!!

Fine's book should be sufficient for most anyone here. Experienced and accomplished players may detect its relative shortcomings and need something more modern but for everyone else the lessons it contains will suffice nicely.
People tend to skip the foundational work. You all have classical knowledge down pat? The hypermodern stuff?
Probably not.

Fine's book should be sufficient for most anyone here. Experienced and accomplished players may detect its relative shortcomings and need something more modern but for everyone else the lessons it contains will suffice nicely.
People tend to skip the foundational work. You all have classical knowledge down pat? The hypermodern stuff?
Probably not.
How does Fine's book compare to FCO? One complaint I have with Mastering the Chess Openings by John Watson is the bazillion number of variations he inserts into each chapter, obscuring the ideas behind the moves. The other complaint is that he does not cover some major openings, i.e., the Petroff.

Fine's book should be sufficient for most anyone here. Experienced and accomplished players may detect its relative shortcomings and need something more modern but for everyone else the lessons it contains will suffice nicely.
People tend to skip the foundational work. You all have classical knowledge down pat? The hypermodern stuff?
Probably not.
How does Fine's book compare to FCO? One complaint I have with Mastering the Chess Openings by John Watson is the bazillion number of variations he inserts into each chapter, obscuring the ideas behind the moves. The other complaint is that he does not cover some major openings, i.e., the Petroff.
Fine's book is higher level and more general - fewer lines, really more about ideas - i.e. what are the main strengths and weaknesses to be seen in the main/popular lines. I've read it cover-to-cover, and although I'm glad to have FCO on my shelf as well, I sincerely doubt I'll ever to do likewise with that fat tome.
Fine's book is an excellent "lay of the land" or overview type of book. The FCO is for digging into the particular chapters that align with your repertoire. That's just my 2 cents. :)

Fine's book seemed like what I was looking for, I just bought it. Some of the complaints on it is that it's outdated, but I would imagine that a lot of these ideas are still the same.

When Fine's book first came out, it was an excellent introduction to a lot of the ideas behind different openings. Now many years have passed, and it has never been thoroughly updated, so the question often comes up as to what book would be a good replacement for it. Paul Van Der Sterren's Fundamental Chess Openings is a valiant try, and some people like John Watson's Mastering the Chess Openings series. I've always liked Bill Hartston's The Penguin Book of Chess Openings, although that is a little old as well. Gabor Kallai's Basic Chess Openings is another book that gets good reviews.

Fine's book should be sufficient for most anyone here. Experienced and accomplished players may detect its relative shortcomings and need something more modern but for everyone else the lessons it contains will suffice nicely.
People tend to skip the foundational work. You all have classical knowledge down pat? The hypermodern stuff?
Probably not.
How does Fine's book compare to FCO? One complaint I have with Mastering the Chess Openings by John Watson is the bazillion number of variations he inserts into each chapter, obscuring the ideas behind the moves. The other complaint is that he does not cover some major openings, i.e., the Petroff.
Fine's book is higher level and more general - fewer lines, really more about ideas - i.e. what are the main strengths and weaknesses to be seen in the main/popular lines. I've read it cover-to-cover, and although I'm glad to have FCO on my shelf as well, I sincerely doubt I'll ever to do likewise with that fat tome.
Fine's book is an excellent "lay of the land" or overview type of book. The FCO is for digging into the particular chapters that align with your repertoire. That's just my 2 cents. :)
Ouch! I recently ordered the FCO after all of the positive reviews over at Amazon - rave reviews.
I figured that the FCO was general, as the reviews have said. Just broad stroke ideas and principles behind main lines, not another encyclopedia of openings filled with variations. I already have the MCO 15 and Mastering the Chess Openings. Too many strings of variations for this beginning chess player Arg!

FCO has much more explanation than MCO. It is also probably easier to follow than John Watson's Mastering the Chess Openings series. There are two or three diagrams on each page to help you follow the lines. Watson tends to give full games, and long lines with no diagrams, but FCO focuses mainly on just the opening few moves.

The Kasparov/Keene book was called Batsford Chess Openings, and had two editions the second of which came out in 1989. It was interesting as well. MCO tends to be revised by American authors: Reuben Fine (6th edition), Walter Korn (7th through 12th), Larry Evans (10th) or recently Nick De Firmian (13th through 15th). The British publisher Batsford also reissued the 15th edition of MCO with slightly different formatting, but that is just the book by De Firmian.

When I bought Fine's book on the ideas behind the chess openings it was the best book available at the time ( mid 70s) on the subject. It helped me tremendously at the time and I was about 1700-1800 OTB. There may well be better books now , I dont know. I am not familiar with FCO nor Watson's series on the openings. I wouldnt worry about the book being "dated" as the ideas behind the openings it covers havent changed. The assessments and popularity of certain variations may change but the main ideas behind the opening(s) basically remain the same....

Fine's book should be sufficient for most anyone here. Experienced and accomplished players may detect its relative shortcomings and need something more modern but for everyone else the lessons it contains will suffice nicely.
People tend to skip the foundational work. You all have classical knowledge down pat? The hypermodern stuff?
Probably not.
How does Fine's book compare to FCO? One complaint I have with Mastering the Chess Openings by John Watson is the bazillion number of variations he inserts into each chapter, obscuring the ideas behind the moves. The other complaint is that he does not cover some major openings, i.e., the Petroff.
Fine's book is higher level and more general - fewer lines, really more about ideas - i.e. what are the main strengths and weaknesses to be seen in the main/popular lines. I've read it cover-to-cover, and although I'm glad to have FCO on my shelf as well, I sincerely doubt I'll ever to do likewise with that fat tome.
Fine's book is an excellent "lay of the land" or overview type of book. The FCO is for digging into the particular chapters that align with your repertoire. That's just my 2 cents. :)
Ouch! I recently ordered the FCO after all of the positive reviews over at Amazon - rave reviews.
I figured that the FCO was general, as the reviews have said. Just broad stroke ideas and principles behind main lines, not another encyclopedia of openings filled with variations. I already have the MCO 15 and Mastering the Chess Openings. Too many strings of variations for this beginning chess player Arg!
I don't want to put anyone off of FCO! I think it's a great book! At this stage, if I had to give one of them up, I'd have to let Fine's go - but like I said, I've already read it. ;)
I took the OP as a question about a book to give an overview of the basic landscape of chess-opening ideas, so Fine seemed like a natural choice. It's really a question of scale, for me. I'm happy to read two pages about the Scotch in Fine (what the heck), but will I read the (larger) six pages on the same in FCO? Less likely - but again, that's just me - and it's not a knock against the book.
It's basically a question of whether you want something that's < 200 pages or > 400. I wanted both. :)
Watson is highly impractical; in the openings he covers he focuses on a few lines that are often not even mainlines, but which he apparently considers most illustrative in a general sense. For instance, in his chapter on the Nimzo he only really discusses the rare Sämisch and Hübner variations (and all the intricate move-orders in reaching them, with long digressions on the value of flexibility in modern opening play). I also dislike the lazy 'illustrative games' approach, which many generalist opening books seem prone to, just adding a few annotations to a random game in a variation and expecting the reader to absorb the ideas by himself.
I think MCO and NCO have little added value to a database since that's better suited to finding lists of moves, since the most-played moves at master level in early opening stages are often the best ones anyway, and the lines there don't go that deep.
Fine 1943 is obviously way too dated. I just browsed through the chapter on the Sicilian to find out exactly how dated it is, and it's remarkable how it illustrates the progress we have made in opening theory:
Sicilian: "There are, further, three important considerations in all variations:
1. Black must never allow White to play P-QB4 (c4) in the opening because then he has no counterplay on the QB file and is thereby doomed to passivity." [there was no such thing as a Hedgehog then]
"2. After white has played P-Q4 (d4), Black must not move ...P-K4 (e5), leaving his QP backward on an open file." [they never heard of the Sveshnikov or Najdorf then or considered such variations positionally suspect]
"3.White must not be passive: he must attack because time is on Black's side (it usually is in cramped positions). That is why the Sicilian is so effective against a pussyfooter." [would Fine consider Karpov's quiet Be2/a4 approach one of a coward?]
"It may also be noted that White should try to get his B on the diagonal KR1-QR8 (h1-a8) as a rule, while it is always bad for him to place it at QB4 (c4). The B at QB4 will rarely help to prevent ....P-Q4 (d5) permanently. Even if it does, it will do so only in a purely passive way." [I don't think Fischer would agree...]
I guess those reading Fine now will be in for a few more surprises.

Having just received the FCO in the mail, I am more than completely embarrassed to say that I now own 16 books on opening theory, plus 7 DVD's on specific openings, plus 2 DVD's on general openings, plus 4 e-books on specific openings.
This is way beyond embarassing. Now that I have said my confession, what is my penance?
Seriously, if you don't own a book on opening theory, I suggest starting with the FCO. GM Paul van der Sterren is absolutely brilliant AND easy to understand. His writing has just the right amount of depth and detail for anyone Class B and below - an estimate. For those Class A and above, well, they know what books to buy.
Is there a book which discusses the ideas of all (or many) of the major openings? Basically, I'm looking for something that briefly (but not so briefly that I could figure it on my own after playing a couple of games) states what the particular opening hopes to accomplish, maybe what to look out for, some of the more important lines, some important games, and possibly anything else helpful.