Tools and techniques are described for merging versions of documents using multiple masters. These tools may provide methods that include syncing a first peer system with at least a second peer system, with the first and second peer systems receiving respective instances of a document for collaborative editing. The first and second peer systems may maintain respective version histories associated with the document, with these version histories capturing and storing revisions occurring locally at the first and second peer systems. The first and second peer systems may exchange version histories, and merge these version histories.