Though it's hard to get a grip on a topic as amorphous as loneliness, social psychologists Rubenstein and Shaver manage to do a fairly credible job--thanks to a five-year study involving 30,000 replies to an 84-question survey, and an unspecified number of personal interviews. The questionnaires were printed in newspapers and popular magazines throughout the country, so it would seem that the geographical sampling is broader than most. The authors present their material in age groups, discussing how and to what degree loneliness affects children, adolescents, adults, and the elderly. The biggest surprise, perhaps, is the elderly: not only is the stereotype of the isolated, friendless older person apparently drawn from a minority, but Rubenstein and Shaver actually discovered that loneliness declines with age. (This finding is attributed to higher self-esteem and a firmer sense of identity.) Adolescents were the loneliest group (this time the culprit is lower self-esteem, along with self-consciousness arising from a new internal self-awareness); marrieds who were also in love with their spouses were much less lonely than singles or marrieds not in love. (And married husbands came off best, since they benefited from their wives' highly developed capacity for intimacy.) Some of the recommended antidotes for loneliness are not altogether run-of-the-mill: enjoy ""active solitude""; avoid the extremes of a clinging or evasive social style; learn how to deal with repeated social and geographical transitions, etc. In a field where the thoughtful pickings are slim indeed, a modest achievement.