Over millions of years of co-evolution with insects, plants have developed various defense machineries that can be activated in response to insect herbivory. Insects, in turn, have developed a variety of strategies to evade these plant defense mechanisms. An improved understanding of this complex plant defense and insect counter-defense relationship will facilitate development of better strategies to improve host plant defense. Currently, we are using Arabidopsis to study plant defense signal transduction pathways against insect pests. Meanwhile, since effectiveness of plant defense is also determined by the insect response, my laboratory is also investigating how insects adapt to the challenge of plant defense molecules, as well as to human imposed management strategies, and is working to identify new insect vulnerable systems.