Summary: Michael Quinn Patton’s Blue Marble Evaluation is a forward-looking, path-breaking, and timely contribution to evaluation theory and practice. The title of the book evokes the Blue Marble shot—a photograph of the whole earth taken by the Apollo 17 astronauts in 1972. The preface of the book displays the first image of our lonely planet captured from space in 1968 (Earthrise). It elicited the following comment by an Apollo 8 crew member: “We came all this way to explore the moon, and the most important thing is that we discovered the Earth.” This is the bracing perspective offered by Blue Marble Evaluation, an audacious publication designed to make evaluation truly matter in a world facing existential risks. Click here to read the full review.