We would like to create 3 separate address lists/books based on 3 different sites ( A/B/C). We would like to set permissions on each address lists so that Users A only see Site A addresses, Users B only see Site B addresses and etc. Then we want to allow certain people to see all the address lists a/b/c and be able to assign specific people to manage/update all address lists. We are running Exchange 2013 on Win2012r2. Let me know if you need further explanation.