So I'm fairly new to iPhone (having had a BlackBerry for 4 years). Since setting my iPhone 5 to sync contacts, email etc with Exchange 2010 I've had a rather annoying issue, it seems that the iPhone picks up the "Suggested Contacts" folder, this means that my iPhone now has a contact for every single person that I've ever send an email to.
I read a couple of articles which suggest the way to fix the issue is to disable the suggest contacts, for me this would work fine, however the majority of my users use the suggested contacts. The solution is actually rather simple.
On the iPhone go to Contacts
Go to Groups
Check all the address books that you don't want to sync.