I've not read the book, but I have read about his system, and I use it in my home management planner for keeping up with all of my duties here at home. I have made some adaptions, since my end goal is not productivity and success in the eyes of the world, but faithfulness to God in serving my husband and family. However, practically speaking, there are alot of tasks that need to be taken care of and remembered. I find the GTD method to be very effective in helping me not allow various things to slip through the cracks.