* Cotton aphid and two-spotted mite were collected from Australian cotton growing regions and tested in the laboratory for insecticide resistance., * For the third consecutive season molecular testing was used to detect pirimicarb and organophosphate resistance in field collected cotton aphid strains. Bioassay and molecular testing were conducted in parallel. Similar results where obtained by both methods in their characterisation of pirimicarb and organophosphate resistant aphid strains., * Pirimicarb and organophosphate resistance associated with control failure was detected in one cotton aphid sample from the Macquarie Valley in 2006-2007. In 2007-2008 aphids were scarce in the Macquarie Valley so no samples were collected. However one strain from St George is pirimicarb resistant and one strain from Gwydir has produced resistant isolates (a mix of susceptible and resistant)., * Prima facie acetamiprid resistance has been detected in cotton aphid for the first time but additional testing is required for confirmation., * Propargite, chlorfenapyr (Intrepid ), abamectin and bifenthrin (Talstar ) resistance were detected in two-spotted mite strains but resistance patterns to the specific chemicals were not the same across seasons