This Healthy Building Network (HBN) Research Brief examines replacements for phthalate plasticizers in Polyvinyl Chloride (PVC) building materials. Plasticizers are added to PVC to make it flexible, but since they are not tightly bound to the PVC molecules, they migrate from PVC products. Phthalates, the most commonly used plasticizers in PVC, are known endocrine disruptors – chemicals that interfere with hormone signaling, which is especially critical to early childhood development. Additionally, many phthalates are known carcinogens and reproductive and developmental toxicants. Exposures to these toxic plasticizers from PVC products can occur throughout their lifecycle. Therefore, it is crucial that PVC products containing phthalate plasticizers be eliminated from the built environment.