Virtual communities (VCs) represent popular social environments in which people interact by exchanging resources such as information, ideas, and advice about their common interests. Existing research lacks an explication of why people help others in VCs and how such voluntary behaviors drive subsequent attitudes (VC commitment) and behavioral intentions (online co-shopping). This article adopts resource exchange theory to examine how two routes of interactivity (structural vs. experiential) influence reciprocity and affect commitment and co-shopping. Using a netnography study and an online survey, the authors confirm the significant effects of structural and experiential routes of interactivity on reciprocity. Reciprocity has critical effects on social system maintenance by enhancing commitment to the community and intention to co-shop. The results also identify partially mediated relationships among various variables, which suggest that the effects of the experiential route on VC commitment and co-shopping operate partly through reciprocity.