Of the one out of seven (latest computation--in fifty years it Will be one out of four) who are in their 60's, many apparently need the assurance that sex does not speak only to and for the young but is appropriate, normal and decent, and that age does not convert desire into lechery. Dr. Butler, who wrote the excellent, all-encompassing book on Why Survive? Being Old in America, now evaluates some of the sexually attenuating processes (hormonal diminution; illnesses from coronaries to backache; drugs; surgery; and emotional problems from boredom to grief). On the therapeutic side there's exercise, nutrition, rest, aesthetics (too much make-up is rightly seen as disfiguring) and counseling if necessary. Without hand-holding, Dr. Butler is assuasive and directive--proceeding from specifics to the overriding fact that continuing sexuality is both an affirmation of self and one's intimacy with someone else at a time when the walls close in.