The currant-lettuce aphid (CLA) Nasonovia ribisnigri (Mosley) is a known pest of chicory, endive radicchio and lettuce. Australia was CLA free until 2004 when it was detected in Tasmania and by 2006 had been confirmed in all Australian states. This report outlines initial research to maintain currant-lettuce aphid in laboratory culture for the reaon of insecticide resistance bioassay development as the first step to baseline generation for the purpose of resistance monitoring. The study successfully derived an Austrlian interim preliminary discriminating dose for imidacloprid for the purpose resistance monitoring.