When you just decided to use Surrogate Keys, another problem arises : which value should I use ? It seems to be a very simple problem since the key now is completely in isolation in your application and is not related to any data. The choice is quite bonding, since a change means that every value has to be changed, and you did not let this key leak outside the database did you ?
The keypoint here is isolation. Many differents kinds of isolation are available, and soon you will be able to make a informed decision.
