A new era is emerging, namely, that of "smart materials", ie., materials that have the ability to "direct" the growth of biological tissue around them in a way to strengthen the tissue-implant interface. This proposal suggests a novel approach involving implanting sensors and sensing materials into an artificial hip which can respond to stimuli and invoke bone growth as is needed to support the prosthesis. If successful, this type of research could revolutionize manufacturing of prosthetic devices and other tissue-material interfaces.