While most adults tend to look askance at non-fiction with this title, most youngsters in the age group (10-15) fully expect to one clay travel in space. And when all the individual contributions toward such ventures are gathered together, the result is impressive and ipso facto important. Halacy describes some of the problems of space exploration, the machines which we will perhaps use on the lunar surface, and the probable contributions of such explorations to the long-range goals of humanity. He touches on the spinoff economic usefulness of discoveries made en route (although he sees no reason to discuss the wider moral issues of priorities in the social sphere). The book is interesting and far from farfetched. Patrick Moore's The Moon, written about 15 years ago, provides startling contrast in emphasizing how far we have advanced.