A vast number of manufacturing techniques have been employed in the last five years to manufacture three dimensional (3D) calcium phosphate (CaP) scaffolds, with the intention to replicate the architecture of native bone as well as to repair and restore bone function. Design features such as architectural control and sintering temperature and their impact on scaffold performance is presented in this review. In vitro cell responses to bioceramic scaffolds and their in vivo performances have been enhanced. Current frontiers of active research on HA scaffolds have included the relationship between fluid flow and mechanotransduction as well as cell signaling pathways that induce endothelial cell recruitment and angiogenesis. Additionally, current research has focused on a better understanding of cell signaling and its environmental cues. The availability of non-invasive and non-destructive quantitative imaging modalities has also become critical in aiding the characterization of scaffolds and predicting scaffold performance. It is thus anticipated that further knowledge gained from this research will allow the overall advancement of scaffolds that can be clinically used to restore large bone defects.