Abstract: In a disclosed method that facilitates collaborative file updating, data is accepted from one of a plurality of users and stored. The data represents an initial version of the file and designates one or more recipients of the initial version. Then, for each one of sequentially updated versions of the file, data representing a difference between the updated version of the file and an immediately previous version of the file is accepted from a user. The data also designates one or more recipients of the updated version. Data representative of the updated version of the file is transmitted to the designated recipients of the updated version. The data transmitted to each recipient who is designated as a recipient of the updated version and who accessed the immediately previous version consists substantially of the difference between the updated and previous versions of the file. Other methods and systems are disclosed.