We welcome you to the proceedings of the Third International Workshop on Self-Organizing Systems (IWSOS 2008) hosted at the University of Vienna, Austria.IWSOSprovidesanannualforumtopresentanddiscussrecentresearch inself-organizationfocusedonnetworksandnetworkedsystems.Researchinse- organizingnetworkedsystemshasadvancedinrecentyears, buttheinvestigation of its potentials and limits still leaves challenging and appealing open research issues for this and subsequent IWSOS workshops. Complexandheterogeneousnetworksmakeself-organizationhighlydesirable. Bene?ts envisioned by self-organization are...