This report represents the Pew Research Center's most ambitious examination to date of America's newest generation, the Millennials, many of whom have now crossed into adulthood. Pew Research Center began looking at this age group in 2006 in a comprehensive survey conducted in association with the PBS documentary series, "Generation Next." This new report greatly expands on that seminal work. In this report, the Pew Research Center sets out to compare the values, attitudes and behaviors of Millennials with those of today's older adults. And to the extent that they can, they also compare them with older adults back when they were the age that Millennials are now. At any given moment in time, age group differences can be the result of three overlapping processes: (1) Life cycle effects. Young people may be different from older people today, but they may well become more like them tomorrow, once they themselves age; (2) Period effects. Major events (wars; social movements; economic downturns; medical, scientific or technological breakthroughs) affect all age groups simultaneously, but the degree of impact may differ according to where people are located in the life cycle; and (3) Cohort effects. Period events and trends often leave a particularly deep impression on young adults because they are still developing their core values; these imprints stay with them as they move through their life cycle. It is not always possible to identify--much less unpack and analyze--these various processes. On many measures, the long-term trend data needed to make comparisons simply do not exist. Also, while generations may have personalities, they are not monolithic. There are as many differences within generations as there are among generations. Moreover, the composition of a given age cohort can change over time as result of demographic factors such as immigration and differential mortality. Finally, even if the Pew Research Center had a full set of long-term data, they know that the discrete effects of life cycle, cohort and period cannot be statistically separated from one another with absolute certainty. Nonetheless, they believe this journey is worth taking. Everyone knows people who still bear the marks of their distinctive coming-of-age experiences: the grandmother raised during the Depression who reuses her tea bags; the child of the Cold War who favors an assertive national security policy; the uncle who grew up in the 1960s and sports a pony tail. It is not know yet know which formative experiences the Millennials will carry forward throughout their life cycle. It is the hope that the findings presented in this report begin to shine a light on what they are like today--and on what America might be like tomorrow. The following are appended: (1) Survey Methodology; and (2) Topline questionnaire.