The literature on emerging adulthood (EA), which emerged after Arnett's (2000) influential article, is now entering its second decade. However, inquiry into the implications of EA for close, romantic relationships is still quite new (Reifman, Colwell, & Arnett, 2008). The purpose of this opening chapter is threefold: (1) to provide a brief introduction to EA; (2) to examine how EA reflects, and perhaps has an impact on, various societal trends; and (3) to suggest some initial conceptual linkages between EA and romantic relationship processes and why EA is important for the study of romantic relationships. Possible socio-demographic considerations in the study of EA and close relationships are briefly discussed in a fourth section. BRIEF INTRODUCTION TO EMERGING ADULTHOOD Emerging adulthood is the period from 18–25 years old (or perhaps older), the tenor of which is captured in the following quote from Arnett (2000, p. 469): “Having left the dependency of childhood and adolescence, and having not yet entered the enduring responsibilities that are normative in adulthood, emerging adults often explore a variety of possible life directions in love, work, and worldviews.” Thus, at its core, EA is a time of exploring, of believing that many possibilities and opportunities are available in life, of feeling in between adolescence and full-fledged adulthood, and of making the transition to assuming greater responsibility for oneself (Arnett, 2004). Stress, anxiety, and instability are also thought to accompany these features of EA (Arnett, 2004; Robbins, & Wilner, 2001).