Recent research has shed new light on individual development during the early adulthood years, yet few investigators have examined sibling relationships during this stage of life. These relationships undergo transformations as individuals enter adult roles and orient their lives towards friends and romantic partners and establish independence from parents and siblings. This review examines major life events and role transitions such as leaving home, completing school, obtaining employment, getting married, and having children that influence individuals and their sibling relationships. In addition, the review considers how sibling relationships may affect individuals during the transition to adulthood, and considers the context of family and culture. The article concludes with suggestions for future research on sibling relationships during early adulthood and beyond.Research on sibling relationships and development during the transition to adulthood has converged to produce a new line of inquiry into the nature and relevance of sibling relationships in early adulthood. Just as individuals undergo multiple changes on their journey toward adulthood, sibling relationships undergo transformations as older adolescents establish independence from their natal family and acquire adult roles. These role transitions often promote a recentering of major life relationships, such as those with family, friends, and romantic partners (Tanner, 2005). However, few researchers have followed siblings as they, one by one, leave their natal family and move into the wider world (Cicirelli, 1996;Dunn, 2007). A host of research questions, ranging from the practical to the philosophical, remain unanswered. For example, what happens when older siblings leave home after high school or college? More philosophically, what purpose do siblings play in family life during the transition to adulthood? As Dunn (1992) stated, "The question of how normative life transitions affect siblings' relationships is an interesting one, on which we have, as yet, little systematic information" (p.3). It is this stage of life, the transition from adolescence to adulthood, where the largest gap in research on sibling relationships exists (Bedford, 1998;Cicirelli, 1996; Connidis, 2001). This article identifies meaningful events and experiences during the transition to adulthood that may affect the nature of sibling relationships and discusses how sibling relationships may affect this transition.