Millions of readers literally defined their lives through Gail Sheehy's international bestseller Passages, named by a Library of Congress survey as one of the most influential books of our times. Seven years ago she set out to write a sequel, but instead she discovered a historic revolution in the adult life cycle.

People are taking longer to grow up and much longer to die, thereby shifting all the stages of adulthood - by up to ten years. She traces radical changes for the generations now in the Tryout Twenties and Turbulent Thirties and finds baby boomers in the Flourishing Forties rejecting the whole notion of middle age. In its place Gail Sheehy discovers and maps out a completely new frontier - Second Adulthood in middle life.

"Stop and recalculate," she writes. "Imagine the day you turn 45 as the infancy of another life." Instead of declining, men and women who embrace a Second Adulthood are progressing through entirely new passages into lives of deeper meaning, renewed playfulness, and creativity beyond menopause and male menopause. But we are all a little lost. The old demarcations and descriptions of adulthood, beginning at 21 and ending at 65, are hopelessly out of date.

Sheehy presents startling facts: A woman who reaches age 50 today - and remains free of cancer and heart disease - can expect to see her ninety-second birthday. Similarly, men can expect a dramatically lengthened life span. To plot our route across these vast new stretches of Second Adulthood, we need a new map of adult life.

1. New Passages tells us we have the ability to customize our own life cycle. This groundbreaking work is certain to awaken and permanently alter the way we think about ourselves as profoundly as did the original Passages.