In this paper, the consensus problem of multi-agent following a leader is studied. An adaptive design method is presented for
multi-agent systems with non-identical unknown nonlinear dynamics, and for a leader to be followed that is also nonlinear and
unknown. By parameterizations of unknown nonlinear dynamics of all agents, a decentralized adaptive consensus algorithm is
proposed in networks with jointly connected topologies by incorporating local consensus errors in addition to relative position
feedback. Analysis of stability and parameter convergence of the proposed algorithm are conducted based on algebraic graph
theory and Lyapunov theory. Finally, examples are provided to validate the theoretical results.