Abstract. The objective of this note is to give several comments regarding consensus and cooperation in networked multi-agent systems, and to mention some closely related results published in 2000 and 2001. This paper focuses on the graph theoretic results underlying the analysis of consensus in multiagent systems. As stated in the Introduction, "Graph Laplacians and their spectral properties are important graph related matrices that play a crucial role in convergence analysis of consensus and alignment algorithms." In particular, the stability properties of the distributed consensus algorithms for networked multiagent systems are completely determined by the location of the Laplacian eigenvalues of the network