Having devoured Holland's earlier book on the modern state of ocean and atmosphere chemical reservoirs,The Chemistry of the Atmosphere and Oceans(Wiley‐Interscience, New York, 1978), and having read several of the stimulating papers that derived from his work on the promised companion volume, concerned with the history of atmospheric and ocean chemistry, I eagerly anticipated publication ofThe Chemical Evolution of the Atmosphere and Oceans. It has been published, and I am not disappointed, nor will the education of any graduate student or practing professional in the earth or ocean sciences be complete without thorough study of this long‐awaited book. There is nothing else that resembles it in subject matter, comprehensiveness, and thoughtful and objective analysis of data and of old and new ideas in the field.Holland has devoted space and consideration in his book to the different episodes in atmospheric and ocean chemical history of the earth roughly in proportion to the relative duration of each episode. This, of course, means that the treatment of the relatively data‐rich Phanerozoic interval is more terse than the sections on the Precambrian. Yet Holland handles the paucity of data for the Precambrian with flair and appropriate conjecture. In fact, it is in this part of the book that his impressive intellect s