How do I avoid duplicates when importing sequences?

We’re doing lots of collaborative editing at our company and just switched from FCP7 to premiere.  We’re able to import sequences into projects just fine, but a HUGE problem arises with duplicates.  Each sequence we import brings in new master clips in the Project window, even though all that media already exists in the project.  If I delete it, the media disappears from the sequences that use it. 

 

WHY!!!!?

 

I assume this is user error.  We’re still learning the software and collectively agree that this can’t possibly be how Premiere is designed to operate.  What are we doing wrong, and how can we avoid balooning our project files each time we want to consolidate our editors’ work?

via Adobe Community : Popular Discussions – Adobe Premiere Forums http://forums.adobe.com/thread/1084568