Phospholipases A 2 (PLA 2 s) are responsible for releasing the fatty acid moiety from the sn-2 position of phospholipids. These enzymes are virtually ubiquitous proteins known from all major biological taxa. Various PLA 2 s act in a wide array of biological processes, including digestion of dietary lipids, cellular homeostasis, intra- and intercellular signaling, host defense and at least a few ecological interactions. PLA 2 activities have been recorded in a small number of insect species, which can be taken to represent the broad group, Insecta. Within insects, PLA 2 s act in functions expected from the background on these enzymes. So far, we know PLA 2 s act in lipid digestion, cellular host defense signaling, reproduction and in organismal-level metabolism. Additional PLA 2 actions are certain to emerge. This is the first article devoted to assembling the known information on insect PLA 2 s. I review the scant information available on the biological actions of PLA 2 s in insects, relate new findings on insect pathogens that disrupt insect immune functions by inhibiting PLA 2 s and mention the few reports of sequence information on insect PLA 2 s. Finally, I offer a brief prospectus on future research into insect PLA 2 s. There are two overarching points in this paper. One, there remains a great deal to learn about insect PLA 2 s and two, some of the findings on insect PLA 2 s will have meaningful practical significance.