Bone morphogenetic proteins (BMPs) are motogens, mitogens, and morphogens that promote the osteoblast-lineage progression of osteoprogenitor cells. The clinical outcome of this molecular osteogenic cascade is bone formation. Administration and localization of BMP to a clinical site to promote an osteogenic regenerative outcome requires a delivery system. Clinically, recombinant human (rh) BMP-2 and -7 (rhOP-1) have been therapeutically administered in combination with type I xenogeneic (bovine) collagen, β-tricalcium phosphate, and calcium hydroxyapatite. The logic for a BMP delivery system (i.e., carrier) is profound. Without a biologically engineered carrier, BMP is ineffective. The intent for the content within this chapter is to emphasize the powerful and natural physiological role that BMP has in osteogenesis and the importance of the carrier to locally contain them. It is only by respecting the power of that physiological role that logically designed therapeutics will evolve that will safely and predictably improve bone regeneration for patients.