To appreciate Frank Herbert's achievement in the Dune trilogy, which concludes with "Children of Dune" …, you have to be a devotee of obsession. On the surface, the Dune books offer an unlikely combination of old-fashioned space opera, up-to-date ecological concern and breathtakingly ecumenical religiosity. The space opera elements include a decaying galactic empire, heroes and villains of nearly superhuman power, and truly formidable monsters. The ecology centers around the planet Dune, which is one vast desert, yet which supports a population of remarkably disciplined human beings known as Fremen….

Herbert's vision of a people forced by circumstance into total ecological awareness is worked out in convincing detail; and since the first book in the trilogy, "Dune," was published in 1965, he can hardly be accused of mere faddishness….

What sets these books apart from their competitors is the obsessive quality of Herbert's imagination…. To read the Dune trilogy is...