I believe this book **USED TO BE** one of the best CCNA books out there, but CCNA has changed and this book failed to catch up. After reading the 4th ed of the study guide, I started trying some of the test engines. I realized there were many questions that I simply had no clue. I went to a book store to grab the 5th ed, but still couldn't find some crucial information that definitely appeared in the current CCNA. As some reviewers already mentioned, NAT is an absolute joke - the guide only mentions three NAT types but you are actually expected in CCNA to be able to configure NAT. There are many other topics that are not covered by the 5th ed. Also (Again, as other reviewers put it), sections of Catalyst1900 series can be omitted - the possibility you see questions about 1900 in the current CCNA is virtually none.

Although this book has some positive traits, the coverage is simply not enough for the current CCNA. Make sure you buy an extra CCNA (ICND) book from Cisco that includes 2005 update to fill some missing topics in this study guide. I don't say reading this study guide is a waste of time - it is still a good book that is easy to read so people new to Cisco will get benefits out of it. You just need an extra book or two if you want to pass the current CCNA. Did you notice that most of reviews that gave the book 4/5 stars were put in here in 2004 or before?

(...)

This book covered everything I needed to pass the exam, with hands-on experience, and the bonus material. What a great written book this is. The best I have ever read.

Nicely written, easy to understand - (...)

I recommend this book highly!!

I passed my CCNA exam yesterday. I had NO practical experience with Data Networks but some academic background.
Tod Lammle has a very nice writing style which gives the same feeling you get with classroom delivered courses. He maintains a very light, humorous style, and doesn't mind reminding you of the same thing a 100 times if he believes it is important. Something I really appreciated ! A lot of what was mentioned as important subjects came up in the exam .. usually in more than 1 question.
The review questions thoroughly cover everything on the respective chapter.
This Edition clarifies a lot of stuff that didnt make any sense (to me!) in past editions.

But ..

1- I got 2 questions about NAT. One was a configuration question, and the other was troubleshooting. Unfortuntely, Mr. Lammle sufficed with defining the different flavors of NAT. Not a single command on the subject.
2- VLSM and route summarization.. I studied that from Carl Timm's BSCI Study Guide.
3- The typos are frightening !! And not everything covered in the errata.

To conclude : The book is a very interesting resource as a first reading, but certainly not enough on it's own for passing the exam.

The exam I took had a lot a questions about NAT which were not covered with enough detail in the book. This book covers cursory items that, while interesting, are not on the exam. I would recommend it only for light reading. Some of the answers were incorrect, even had typos or references to routers in diagrams that didn't exist.

I should have skipped the book.

If you already do some of this type of work, and can use Cisco's CCNA prep site, and can use a sim (or your own routers), you'll be in better shape for the exam (in my humble opinion.)

This book does a very good job of mapping to the exam pretty closely without going into too much detail on things you don't need to know, or skipping too many things that are vital to pass.

Todd's method of discussing topics are tactfully approached so they are not confusing to the reader, and his explanations are clear and easy to understand.

The book came up a little short on NAT configuration, and you might want to go over some of the switching stuff again before taking the exam.

Overall though, I would say if you already have some experience you could probably just read this book cover to cover and take the exam (640-801).