Can somebody please advise the best way to do the following

I have a document, and many collegues have a copy of the same document. Each
person updates their own changes to their own copy using track change. BUT I
then have to take each document and type in the changes to the main document.
Is there a way each person can add their own information to the one document
at the same time. The problem is due to deadlines they need to do this at the
same time.

This is duplicating the effort. I've read other responses and Shared
Workgroups are mentioned, but I know aboluletley nothing about these.

Many thanks
JulieG