The Harvard Study of Adult Development is  an extraordinary scientific endeavor that began in 1938 and is still going strong (Waldinger is the fourth director, and Schulz its associate director). For over eight decades, the Harvard Study of Adult Development has tracked the same individuals and their families, asking thousands of questions and taking hundreds of measurements—from brain scans to blood work—with the goal of discovering what really makes for a good life. 

 

Through all the years of studying these lives, strong relationships stand out for their impact on physical health, mental health, and longevity. Waldinger boils it down simply: 

“Good relationships keep us happier and healthier. Period.”