Which feature allows users to collaborate in Revit in real-time?

Worksharing is the feature in Revit that facilitates real-time collaboration among multiple users working on the same project. This functionality allows different team members to access, modify, and update the same central model simultaneously. As changes are made, they can be synchronized to the central model, ensuring that all users are working with the most current information and allowing them to see each other's contributions in real-time.

In contrast, file linking is primarily used for referencing external files into a Revit project, which does not inherently allow for simultaneous collaboration. Element synchronization refers to how individual elements are updated within the project but does not encompass collaborative work by multiple users. Project phasing is focused on managing different stages of construction within a project, rather than facilitating real-time teamwork among users. Thus, Worksharing stands out as the essential feature tailored for collaborative efforts in Revit.