Recently there has been great interest in the reactivity of transition-metal (TM) centers towards white phosphorus (P-4). This has ultimately been motivated by a desire to find TM-mediated alternatives to the current industrial routes used to transform P-4 into myriad useful P-containing products, which are typically indirect, wasteful, and highly hazardous. Such a TM-mediated process can be divided into two steps: activation of P-4 to generate a polyphosphorus complex TM-P-n, and subsequent functionalization of this complex to release the desired phosphorus-containing product. The former step has by now become well established, allowing the isolation of many different TM-P-n products. In contrast, productive functionalization of these complexes has proven extremely challenging and has been achieved only in a relative handful of cases. In this review we provide a comprehensive summary of successful TM-P-n functionalization reactions, where TM-P-n must be accessible by reaction of a TM precursor with P-4. We hope that this will provide a useful resource for continuing efforts that are working towards this highly challenging goal of modern synthetic chemistry.