This paper proposes a decentralized voting mechanism called PeerVote for peer-to-peer collaboration systems. PeerVote allows users to vote on modifications to shared documents. It defines roles for peers including tracker, storage, user, editor, mediator and voter. The voting process begins when an editor submits a proposed change and becomes the mediator. The proposal is then sent to previous editors to vote on within a time period. For a change to be accepted, it must reach a threshold of positive votes. Simulations show PeerVote scales well with increasing peers and maintains robustness even with malicious peers.