There is currently, it appears, a preoccupation with occupational shifting, as seemingly well-educated and successful managers and technocrats seek new careers of ""self-expression"" during the midlife transition years so fully documented by Gail Sheehy and Daniel Levinson. Career counselor Robbins first provides a cogent popular synthesis of current theories of adult vocational development. She reviews the midlife career alteration processes of some of the 91 middle-to-upper-class men whose metamorphoses she has investigated. Finally, she provides a bit of a guidebook on how to do it and where to go for help. The need for further education, the necessity of a financial cushion, and the role of the family are discussed. Everything is copiously illustrated with case histories from the author's study and extracts from the works of others. It's a text to suit the reveries of many an otiose employee, as he wistfully scans those employment ads in the Wall Street Journal each Tuesday. He, too, may change from a pin-striped caterpillar to a butterfly with a lifestyle to suit.