In many of today’s work setting, workers are required to spend a considerable part of their day engaged in social interactions and managing social relationships with customers (Schneider, 1994), and with teams (Kozlowski & Ilgen, 2006). Furthermore, increases in globalization (Javidan, Dorfman, de Luque, & House, 2006), boundaryless organizational structures (Macy & Izumi, 1993), and workplace diversity (Mahoney, 2005) have increased the ambiguity and complexity of workplace interpersonal interactions. As a result, in today’s workplace there is a great need for employees to be interpersonally adaptable (Klein, DeRouin, & Salas, 2006). Though many assessment practices and measures intended to assess individual effectiveness in social situations exist, many of these measures and practices do not assess the situationally-specific and goal-oriented aspects of interpersonal adaptability. There were two primary purposes for the dissertation. First, this dissertation introduces a framework of interpersonal adaptability. In doing so, this framework was meant to highlight three opportunities to improve the assessment of interpersonal adaptability. Specifically, in order to conduct construct-valid ratings of interpersonal adaptability there is a need to design more contextualized assessments, improve the match between construct and method, and incorporate dynamic aspects. The second key purpose was to apply some of these opportunities to current assessment practices. Two empirical studies were included in this dissertation. For the first empirical study, role play assessment exercises were revised to account for context created by role players’ portrayed disposition. It was found that the portrayed disposition of the role player accounted for a significant amount of the between-exercise variance in participants’ demonstrated interpersonal behaviors and performance. For the second empirical paper, a validation study was conducted with measures from a multi-mini interview (MMI), which is a multi-stationed interview used to assess non-cognitive skills of applicants to health professional schools. An analysis of the MMI measures’ convergent and discriminant validity suggested that it continues to be unclear whether MMI measures assess participants’ interpersonal behaviors or interpersonal processing. Implications for future research and practice are discussed. / My dissertation is comprised of three separate, but conceptually related, manuscripts. The first manuscript is a conceptual paper that draws upon sections of my introduction from my proposal. It is targeted to be included as a chapter in an upcoming book. The second and third manuscripts are empirical studies that draw upon some of the findings from my dissertation research. A general discussion was also prepared in order to highlight the key conceptual, empirical, and practical implications from my dissertation research.