Inorganic phosphate is a fundamental building block in biology. It is used for storage of energy (ATP), genetic information (DNA, RNA), cell signalling, and many other roles that are essential for life. Not surprisingly, microbes have evolved enzyme systems to produce inorganic phosphate from alternate forms of phosphorus such as phosphonates. Enzymatic degradation of phosphonates, a class of molecule that is characterized by a highly stable carbon-phosphorus (CP) bond, is very interesting from a mechanistic perspective, as well as a potential means of degrading toxic phosphonates, such as herbicides, insecticides, and nerve agents. We are currently studying two bacterial pathways: (1) the radical based CP-lyase pathway, and (2) the oxidative PhnY / PhnZ pathway. We are also using genomic screens to identify new types of CP-bond cleaving pathways, and thus discover new enzyme mechanisms.