Macro-level trends such as globalization, technology, demographic shifts, and alternative work structures have led researchers and practitioners to challenge traditional definitions of individual work performance (Ilgen & Pulakos, 1999). Two major ways in which these definitions have shifted include performing in interdependent and uncertain work contexts (Griffin, Neal, & Parker, 2007). In this chapter, we explore such expanded definitions of work performance by considering what we know (and what we do not know) about adaptive and organizational citizenship-related behaviors and how this knowledge might be used to inform selection.