Just outstanding; one of those down-to-earth, published-just-before-Vatican-II texts (there are many of these, I'm finding, at least from English language authors and usually published by Sheed & Ward) you find in a used section and turns out to be nothing but treasure from start to finish. This is the most useful, practical, simple, and insightful manual on prayer I've read that isn't by Fr. Jacques Philippe. It might even be better than that, in spite of a rather technical learning curve with language. Dom van Zeller, a Benedictine, is very careful in laying out the Church's traditional schema for prayer and sometimes this means slowing down to absorb and reread more theologically-oriented sections, but as it proceeds one finds momentum building and it becomes much easier in the second half to insert one's own life situations into the framework, effects, and dangers he describes. I will be drawing from this one for the rest of my life.