||The key defining features of a successful biomaterial are favorable interactions with the host body or tissue with which it comes into contact while also retaining the ability to perform a function as a therapy or part of a medical device. A favorable interaction, aka biocompatible, has been classically defined as one that is inert. However, the implantation of any medical device into the body will elicit a response. The goal of the biomaterials community is to learn how to facilitate that response to mitigate deleterious interaction, promote integration into the host tissue when appropriate, and facilitate device performance. The longevity and severity of that response are dictated by both biotic and abiotic factors. For decades, biomaterialists have studied the effects of the implantation procedures, the composition and design of the device, the duration of implantation, the location of the implanted device, and the intended application of the implanted materials and devices. It has become increasingly more clear that the response is not just an initial interaction, but a long term dynamic and self-perpetuating communication between the host tissue and implant material. In this symposium, the Society for Biomaterials will collectively present our current understanding of the “Biological Response to Materials and Material’s Response to Biological Environments.” Particular emphasis will be placed on the development of novel materials that facilitate the biotic and abiotic interactions, on cutting edge techniques to gain new perspectives on these mechanisms, and on how the dynamic response facilitates device performance.