Short chapters: each one exploring one aspect of the GTD (Getting Things Done) methodology. It's a collection of David Allen's newsletters throughout the years. It contains various of his famous quotes and some of his A-HA moments working with the methodology.
The last chapter brings a GTD summary with the 5 steps, the weekly review, the natural planning model and the higher horizons. It still uses the old nomenclature before David Allen published the revised edition in 2015.