How does it work in Ireland?

I'm curious as to how the system functions there, if you want to specialize. After you complete your internship, are you matched as in the US or do you apply for a registrar's post at a particular hospital in the field that you want to specialize in? Does the same apply for IMG's (after they have obtained the necessary registration)? How long does it generally take to specialize?

Pardon me if I sound a little ignorant. Any comments and input would be greatly appreciated!

Regards
Mae