Like the Bob Newhart "Stop It" skit she describes near the beginning, the real answer to clutter is "Don't do that." If something's going to cause financial or space problems, or otherwise make a mess of things, the sanest response is just not to do it. However, human beings don't always act sanely, and you may find yourself coping with your own or somebody else's past or present clutter problems. Lipp, being a Christian writer, would also point out that bad stewardship is a form of disobedience (and can include covetousness, dishonesty, and stealing), and that the hoarding of Stuff, which we might justify by calling it prudence, is not God's best for us. I appreciated her thought that simplicity is not all about "one size fits all." For instance, she has no problem with keeping a certain number of physical books around (whereas some clutter guides will happily assume that everything one wants to read can be gotten from the library). Lipp sees value in cultivating her interest and skill in cooking, and therefore spends time and space on that; on the other hand, as a poor seamstress, she has little use for a sewing machine. The takeaway I get from her book, rather than Newhart's stern "Stop It," is a gentler "It's Okay." It's okay to let go. It's okay not to let sharp advertising pull your dollars in the wrong direction. It's okay to say you're already okay (and don't need more).
If you need an "It's Okay" to help get things back on track, Clutter Free may speak to your heart.