Abstract This paper examines the benefit of sequentiality in the social networks. We adopt the elegant theoretical framework proposed by We then examine the structure of optimal mechanism and allow for arbitrary sequence of players' moves. We show that starting from any fixed sequence, the aggregate contribution always goes up while making simultaneous-moving players move sequentially. This suggests a robust rule of thumbs -any local modification towards the sequential-move game is beneficial. Pushing this idea to the extreme, the optimal sequence turns out to be a chain structure, i.e., players should move one by one. Our results continue to hold when either players exhibit strategic substitutes instead or the network designer's...