Hi all, this paper "Current progress in network research: toward reference networks for key model organisms" (http://bib.oxfordjournals.org/cgi/content/full/8/5/318) was published in august 2007, so it's not completely up-to-date. Still I think it might be an interesting "overview" paper. You guys probably have a better idea about this. It introduces some general concepts in Systems biology, illustrated with quite some figures. The most interesting part for me, was (at the end) the description of reference networks that should be constructed using some sort of Network Ontology. The authors make a very valid point there, but I don't think much work has been done yet in this field. I might be wrong though ;-) This ontology-bit could be listed as both an opportunity and a threat, I think :-) Sofie