I read a lot of books on organizing, and this surprised me by how useful it was. While there are plenty of cleaning and organizing techniques given in this book, Felton focuses on identifying the mental attitudes and personality traits that lead people to become either organized or messy. She then shows how organized people approach cleaning and organizing problems, and contrasts that with the ineffective approaches that "messies" -- the chronically messy who want to be organized and clean but don't do it -- err in the same situations.
A couple of examples. A "messie" might make a schedule of housecleaning tasks to be done. Then, passing a dirt glob on the carpet, think, "I see that. According to the schedule, I'll be vacuuming tomorrow and that will take care of that," and walk on by it (and lots of other problems). A person who is effective at housecleaning, and whose goal is to keep a constantly clean and organized space, will simply clean it up as quickly as possible, probably as soon as they see the mess. A simple difference, you might think, but the results are profound. Also, a messie might wonder how he can ever find time to clean, say, a bathroom. A neatie will take advantage of a few spare minutes to quickly do some part of that task, so that, in a day or two, it is done. Simple stuff, sure, but insightful and useful to those who do not habitually think that way.
Felton's ideal is to have a house that is always clean and neat -- a house where, when someone drops by unexpectedly, you simply invite them in, without worrying about what the house looks like, because you know it is clean and neat. That simple and very worthy goal is overwhelming to a lot of people. This book can motivate, encourage and teach you how to accomplish it.
The book is simply written, and she does a lot of handholding for her "messies" readers, and that might put some people off. But she knows, as a former messy herself, that this subject can be extraordinary intimidating and is the cause of much stress, despair and self-loathing for many people. Better to err in the direction of too much comforting than too little.
Some of the ideas in this edition are outdated, but most are not. She has continued writing on the topic, and updated books from her are available. If the above resonates with you, check it out.