"Simplify Your Life: 100 Ways to Slow Down and Enjoy The Things That Really Matter" by Elaine St. James. I read this book and a couple of others by her back in the mid 90s. It changed the way I look at all material things. It was a long process, but I went through every cupboard, closet and drawer, and got rid of everything that was not useful or beautiful. I would imagine that was about 75% of what I owned. I donated it to the local thrift store. The trick to living this way is to apply this same criteria (useful or beautiful) to all new purchases or acquisitions. When I see something I think I want, I usually wait at least a week, maybe two, and see if I still want it. More often than not, I don't. The area that I still struggle with is clothing, but I'll keep trying. One good thing recently came of this; I bought a couple of decent bras that actually fit and got rid of all of the rest of the pitiful things I didn't pay enough for or try on.