Triggering a Method when a Core Data Property changes.

Hi.

I am trying to trigger a method when A Core Data property is
changed, e.g A Text Fields Text in a Table (connected to Core Data) is
changed. Basically I want to be Key Value Observing the CD 'name' property of all
the objects in my Tree Controller, so that when the 'name' property of
one of my objects is changed it triggers an action. How would I do this though?

Cheers.