In this review, we distill existing research on gratitude and its role in organizations. We begin by examining how gratitude is conceptualized and defined, considering its manifestations as an emotion, an expression, and a feature of a collective. We next develop a model arguing that gratitude is best understood as a phenomenon that begins within the self but has the potential to cascade beyond the self and emerge at higher levels of analysis. After reviewing the key theories that underpin gratitude scholarship, we explore existing research on gratitude's functions. We follow with a consideration of gratitude's antecedents. Finally, we conclude with a discussion of promising trajectories for future research, emphasizing important directions for both theory and practice.