We are proud to present the proceedings of NET-COOP 2009, the inter- tionalconferenceonnetworkcontrolandoptimization, co-organizedbyEURAN- DOM/Eindhoven University of Technology and CWI. This year's conference at EURANDOM, held November 23-25, was the third in line after previous e- tions in Avignon (2007) and Paris (2008). NET-COOP 2009 was organized in conjunction with the Euro-NF workshop on "New Trends in Modeling, Quan- tative Methods, and Measurements. " While organized within the framework of Euro-NF, NET-COOP enjoys great interest beyond Euro-NF, as is attested by the geographic...