It has proven quite difficult to either increase or decrease expression of Pf NHE protein to further test how Pf NHE may be linked to QN resistance, but a new paper reports decreased PfNHE levels for three parasite strains (GC03, 1 BB5, 3 BA6) by stable transfection with a truncated 3´-untranslated region [100] . The transfectants from these experiments do not show statistically significant changes in resting (steady state) pH cyt as would be expected based on previous work [52] , but they do show small increases in QN sensitivity consistent with Pf NHE protein being involved in QN resistance as proposed [60, 52] . Unfortunately, in [100] only strains with low levels of QN resistance were amenable to transfection, whereas decreased Pf NHE expression for strains with Executive summary n Over the past 9 years, a clear picture of the genetic alterations that accompany evolution of chloroquine (CQ) resistance in Plasmodium falciparum malaria has become available. P. falciparum CQ-resistance transporter (PfCRT) mutations must be present and these confer a tenfold decrease in CQ-mediated growth inhibition and toxicity. Mutations and/or elevated expression of P. falciparum multidrug-resistant protein 1 (PfMDR1), perhaps along with mutations in P. falciparum Na + /H + exchanger, further tailor quinoline drug resistance, and perhaps resistance to other classes of compounds that also target the parasite digestive vacuole.