How do you keep the focus?

As a leader of a school, it is your responsibility to support your teachers in keeping the focus on student achievement and high-quality instruction.  How do you do it?  How do you support teachers to maintain this focus and protect them from distractors or events that might take their focus away from their core work?  This is an essential role for a leader - to support and protect teachers so that they can do the essential work of ensuring every child is successful.