This study explores whether the dynamic path to group affect, which is characterized by interactive affective sharing processes, yields different effects on task performance and group dynamics than the static path to group affect, which arises from non-interactive affective sharing. The results of our experiment with 70 three-person work groups show that groups performed better on creative tasks than on analytical tasks when they were in a positive mood, and better on analytical tasks than on creative tasks when in a negative mood, but only when affect was interactively shared. Moreover, analysis of videotaped group member interactions during task performance showed similar results for work group dynamics, such that group affect influenced belongingness and information sharing only when affect was interactively shared and not when affect was non-interactively shared. Results support the idea that affective sharing processes are fundamental for understanding the effects of group affect on behavior. Copyright © 2010 John Wiley & Sons, Ltd.