Which characteristics do you admire the most in leaders?

I admire how deep the knowledge of a leader of his/her own organization is. I can say this aspect can tell you a lot about a good/bad leader. How many leaders would know if today's a member's birthday? How many bosses would say words of appreciation for the efforts that have been carried although it was not successfull? It is an important trait of a good leadership so that it can take place.