The Grant Study is an -year continuing longitudinal study from the Study of Adult Development at Harvard Medical School, started in 1938. It has followed 268 Harvard-educated men, the majority of whom were members of the undergraduate classes of 1942, 1943 and 1944. It has run in tandem with a study called "The Glueck Study," which included a second cohort of 456 disadvantaged, non-delinquent inner-city youths who grew up in Boston neighborhoods between 1940 and 1945. The subjects were all white males and of American nationality. , the men continue to be studied. They were evaluated at least every two years by questionnaires through information from their physicians and by personal interviews. Information was gathered about their mental and physical health, career enjoyment, retirement experience and marital quality. The goal of the study was to identify predictors of healthy aging. The study, its methodology, and results are described in three books by a principal investigator in the study, George Vaillant. The first book, Adaptation to Life, describes the study up to a time when the men were 47 years of age. The second book, Aging Well, describes a time when the inner-city men were 70 years old and those of the Harvard group were 80. In 2012, Vaillant and Harvard University Press published the third book, Triumphs of Experience, which shared more findings from the Grant Study. The study is part of The Study of Adult Development, which is now under the direction of Dr. Robert J. Waldinger at Massachusetts General Hospital. The study is unique partly because of the long-time span of the cohort, and also partly because of the high social status of some of the study participants. Among the most notable Grant Study participants included Ben Bradlee, an editor of The Washington Post, and US President John F. Kennedy.

Main results

George Vaillant, who directed the study for more than three decades, has published a summation of the key insights the study has yielded in the book Triumphs of Experience: The Men of the Harvard Grant Study: