Technical Abstract: We tested the affects of nitrogen levels and water availability on the ability of cotton plants to deter feeding by Spodoptera exigua larvae through induction of anti-feedant chemicals by the cotton plant, and to attract the biological control agent, Micropitis crociepes through induction of chemical volatile emission. Cotton plants were grown with 0, 1 and 2 times the recommended nitrogen levels and had water stress or normal water. Choices of leaf tissue from the various nitrogen and water treatments were provided to S. exigua larvae. Choices of the plants with various nitrogen and water treatments were provided to M. croceipes in flight tunnel bio-assays. Both water stress and nitrogen levels under and over the recommended levels increased leaf tissue consumption by the S. exigua larvae, and decreased attraction of M. crociepes to the cotton plants. Water stress showed an increase in larval feeding compared to plants with normal water. Gas Chromatograph and Mass Spectrometer analyses of the chemical volatiles released from herbivore damaged plants indicate that their concentrations differ among the N levels with the control, 0N and 2N plants having amounts much lower than the 1N plants. Because plant chemical defense mechanisms are negatively affected by improper nitrogen and insufficient water, these factors will need to be considered in biologically-based pest management.