Account to Contact address relationship

Hello again everyone!

I'm still relatively new to CRM administration, and I have a quick question regarding the Account and Contact entities. 

Some of our customers change addresses every so often.  When this happens, we update the address on the Account page.  How would I go about having CRM automatically update the address of the Contacts associated with the Account as well? 

I guess an easier way of putting it would be; How do I create a 1:1 relationship between the address of the Account and any Contacts tied to the Account?