What does it mean to be an adult? Society’s views on that have changed over the past half century. At least 95% of Americans say finishing school and gaining financial independence are key markers of adulthood, but as of 2017, more than half say marriage and parenthood are not very important (Vespa, J., The Changing Economics and Demographics of Young Adulthood: 1975–2016, U.S. Census Bureau, 2017opens in new window).
No matter how it is defined, becoming an adult is a process. Psychologists think about this period, spanning roughly ages 18 to 29, in various ways, including young adulthood, late adolescence, and the transition to adulthood. But one term—emerging adulthood—captures something distinct: an extended period of exploration and uncertainty shaped by today’s social and economic realities.
“This demographic space has opened up where people are less dependent on their parents but have not yet entered the settled roles of adult life, making the 20s different than they were before,” said Jeffrey Jensen Arnett, PhD, a professor of psychology at Clark University in Worcester, Massachusetts, and the author of Emerging Adulthood: The Winding Road From the Late Teens Through the Twenties (Oxford University Press, 2014), who proposed the term “emerging adulthood” in 2000 (American Psychologist, Vol. 55, No. 5, 2000).
Cultural narratives often frame this decade as life’s peak, but today’s emerging adults face a different reality. High housing costs, a tough labor market, and a broader climate of uncertainty are causing many to delay classic adult milestones, including marriage, home ownership, and independent living. In 2023, 18% of 24- to 35-year-olds lived with a parent, up from 11% in 2005 (Fry, R., “The Shares of Young Adults Living With Parents Vary Widely Across the U.S.,” Pew Research Center, April 17, 2025opens in new window; Hemez, P., & Vespa, J., Changes in Milestones of Adulthood, U.S. Census Bureau, 2025opens in new window).
This group reports elevated rates of loneliness and mental health concerns that often surpass those of other age groups (Witters, D., Gallup, April 4, 2023; “Mental Illness,” National Institute of Mental Health, 2024opens in new window). In response, psychologists are working to understand both the vulnerabilities and opportunities of this life stage—how young people develop, what healthy transitions look like, and how families and institutions can offer better support.


