It has repeatedly been shown that demineralization improves the ability of bone auto- and allografts to regenerate natural bone tissue. Conversely, much work in the field of bone tissue engineering has used composite materials consisting of a mineralized phase or materials designed to mineralize rapidly in situ. In this review, we seek to examine these disparate roles of mineralization and the underlying factors that cause this discordance and to examine methods and principles of the mineralization of synthetic polymer scaffolds. Biomimetic approaches to mineralization and phosphorus-containing materials are highlighted, and a brief section focusing on drug-delivery strategies using mineralized scaffolds is included.