Dear All, Three groups of scientists need to write documents collaboratively. They are going to use MS PowerPoint, Word, also store PDF files. They want to be able to add external people from other groups they collaborate with and give them access to some areas or "projects". In other words, they want some collaborative work environment, mostly to work on documents. In the past scientists were using TeX, and one of version control systems (CVS, subversion,...). And all was great, as TeX files (pretty much like programs software developers write) are ASCII text files, and diff of two version is rather small... Unlike the past scientists I work for plan to use MS PowerPoint, Word, also store PDF files. All these are effectively binary files for version control systems, then versions will not be stored as a small diff, but each version ends up being the whole document. One obvious solution may be: just buy office365.com service, or set up MS server on our own machine. And these are the two things I am trying to avoid. Could someone recommend open source software? Some collaborative suite focused mostly on working on documents, with web based interface. I run owncloud server for my Department, and one in general can use that, but I hope to find something more focused towards collaborative work. Thanks a lot for your advises and pointers. Valeri ++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++