This paper studies output feedback consensus protocol design problems for linear multi-agent systems with directed graphs containing a leader whose control input is nonzero and bounded. We present novel distributed adaptive output feedback protocols to achieve leader-follower consensus for any directed graph containing a directed spanning tree with the leader as the root. The proposed protocols are independent of any global information of the graph and can be constructed as long as the agents are stabilizable and detectable. (C) 2016 Elsevier Ltd. All rights reserved.