More than one person can work on a Visio diagram at the same time, each person at their own computer. By coauthoring, teams can create multi-page diagrams quickly and help each other decide what the diagram should look like as they work. Changes made by each person show up in everyone else’s copy of the diagram right away.
Everybody who’s going to work on the diagram needs to have Visio Professional edition installed on their computer.
Setting up a diagram for coauthoring
Create a Visio diagram in a SharePoint library, or start a diagram in Visio and then upload it to OneDrive.
Give all the people who will be working on it permission to edit it.
Each author opens the diagram from the server in Visio and starts creating, editing, or reviewing. A notification down in the corner shows when someone joins or leaves a session (which basically means they open the diagram for editing or close it). You can always see in the status bar how many people are working on the diagram.
How changes show up in the diagram
Small icons appear by shapes that have been edited in some way by another person. You are not locked out of a shape that has an icon that shows it’s being edited – for example, even if someone else is changing the color, you can edit the text on the shape at the same time. If everyone on the team is collaborating and working on specific areas, you should rarely have a problem where two people edit exactly the same thing at the same time, like changing the text on the same shape. If that does happen, the last change is the one that stays (until someone changes it again).
Every time you save the changes you made to the diagram, Visio synchronizes the changes back to the server. At the same time, Visio brings the changes everyone else made into your copy of the diagram. You can tell when someone else has saved changes back to the server by icons that appear, and a notification in the status bar that lets you know updates are available. Save frequently to make sure you have the most recent changes that other authors have made, and to make your changes available to them.