When Tyler deals with the ever-precarious state of human safety and well-being, she shows how mysteriously disaster awaits us, whether in the genetic makeup of an infant or in the presence of a dangerous intruder. One of Tyler's best and most moving stories, "Average Waves in Unprotected Waters" (1977), confronts the problem of a mentally deficient child and follows the mother, driven to the limit of her resources, as she commits her son Arnold to the state institution. The disorder of agoraphobia is pervasive in Tyler's fiction, from the severe condition Jeremy Pauling suffers in Celestial Navigation to the somewhat lesser form of this disorder that Ira's sister, Junie, suffers in Breathing Lessons. Jeremy has not left his Baltimore street block for years; Junie will not step out of the Baltimore apartment unless she has dressed in full disguise, replete with a flaming red wig. As irritating and...