Enchantress From the Stars by Sylvia Engdahl

Only a very few people are capable of combining science fiction and fantasy, and even fewer can make it something that captures you as this book does. The book starts off with a young woman on a planetary anthropological mission, on a world called Andrecia. Andrecia is medieval and primitive, and in no way capable of handling the knowledge that advanced, spacefaring societies exist beyond their world. But the heroine, Elana, soon becomes involved in a plot concerning the potential invasion of Andrecia. But it is near-impossible for her to save the Andrecians, superstitious and magic-believers, from an invasion. Nearby is also a medical guy, Jarel, who feels remorse at the intentions of the Exploration Corps. They do not consider the population of Andrecia to be sentient and worthy of their notice, and promise to bring destruction down on Andrecia. There is also the son of an Andrecian woodcutter named Georyn, who identifies Elana as the Enchantress of the Stars. He believes that she has come for the purpose of testing him, if he can defeat a fearsome dragon in the forests. This clash of the sophisticated and the simple is well-drawn and almost saddening at times. Georyn's faith in Elana's "magic" is truly touching, without making him appear ignorant or dumb. Elana is an excellent, intelligent heroine who captures your sympathy and does not let go. Her struggles with integrity and truth do not transcend the reader, but are ones that you feel as much as she does. Too often in books there is a clash between magic and science, but in this particular book there is no clash. Perhaps that is partly due to the writing style -- half the magic seems to be in the otherworldly descriptions, interspersed with more grounded prose in the right places. (And Engdahl definitely knows how to write a beginning that will suck you in) Though some things like "Imperial Corps" and "Federation" imply a pseudo-Star-Trekkian space opera, this is none of the kind. This is a thoughtful work, filled with intelligent questions that will stimulate as it entertains. This goes on the shelf beside Tolkien and the Riddlemaster trilogy.