Thirty-two stepdaughters and 17 stepsons participated in this grounded theory study of emerging adult stepchildren's perceptions about how relationships with their stepparents developed. The theory created from this study proposes that the degree to which stepchildren engage in relationship-building and -maintaining behaviors with stepparents is a function of stepchildren's evaluative judgments about the stepparents' positive contributions. Stepchildren's judgments about stepparents are made with inputs from biological parents and other kin. Stepchildren's ages when relationships began, gender of stepchildren and stepparents, and time spent together because of custody arrangements provided the context within which relationships developed. The outcomes in this grounded theory were six patterns of step-relationship development: accepting as a parent, liking from the start, accepting with ambivalence, changing trajectory, rejecting, and coexisting. These patterns of development were distinct trajectories that related closely to qualitatively different stepparent-stepchild relationships. Only 30% of stepchildren with multiple stepparents evaluated them similarly. Key Words: grounded theory, remarriage, stepchild, stepparent. adore Jim. I despised Bill. Greta was great. Laura 1 did like: I disagreed with her on a lot of stuff, but 1 did really get along with her. And Babbette just isn't a pleasant person. - Nina, about her stepparents. Although clinicians (Visher & Visher, 1996) and researchers (Crosbie-Burnett, 1984) have long focused attention on stepparent -stepchild relationships as key to overall stepfamily functioning, surprisingly little research exists on the processes by which these relationships develop (Ganong & Coleman, 2004; King, 2006). Given that almost one third of U.S. children will live with a stepparent before they reach adulthood (Bumpass, Raley, & Sweet, 1995) and that lower levels of well-being among stepchildren compared to children in nuclear families have often been attributed to adjustment problems related to acquiring a stepparent (Ganong & Coleman), it is important for researchers to better understand how step-relationships develop, particularly step-relationships that are satisfying for the individuals involved. Knowing how affirming step-relationships develop is useful for practitioners and researchers. Stepparents ' Contributions to Step-relationships Several researchers have reported that steprelationships are closer when stepparents take a supportive role with stepchildren and let biological parents do most of the disciplining (CrosbieBurnett & Giles-Sims, 1994; Hetherington & Clingempeel, 1992). Additionally, authoritative stepparents - who favor high warmth and flexible control as a parenting style - have better relationships with stepchildren than authoritarian stepparents, who demonstrate low warmth and high control (Golish, 2003; Henry & Lovelace, 1995). Some stepparents recognize that their stepchildren are more willing to accept them if they treat them warmly (EreraWeatherly, 1996; Svare, Jay, & Mason, 2004) and engage in friendship-building strategies early in the relationship (Ganong, Coleman, Fine, & Martin, 1999). These research findings echo clinicians' advice for stepparents to befriend stepchildren and try to build close relationships with them before attempting to discipline them (Visher & Visher, 1 996). Although the idea that stepparents should engage stepchildren in activities that are supportive and fun until relational bonds are firmly established may seem logical, not all stepparents do this (Ganong et al., 1999). Many stepparents quickly try to set rules and administer discipline (Berger, 1998; Bray & Kelly, 1998; Erera-Weatherly, 1996; MacDonald & DeMaris, 1996), which often results in conflict and emotionally distant relationships (Bray & Kelly, 1998; Ganong et al. …