A processing technique based on the principle of phase separation was developed to fabricate three-dimensional microcellular foams to act as templates for cell transplantation. The polymers used to make the foams were polylactic acid (PLLA) and a polyphosphoester (BPA/ PP). The resulting foams had relatively uniform, open cells throughout the matrix. The foams could also be fabricated into complex shapes to meet specific design requirements. The foam morphology and microstructure were characterized by mercury porosimetry and scanning electron microscopy. Osteoblast like cells ROS17/2.8 were successfully cultured in the foams. Cell attachment to the foam interior was verified by confocal microscopy.The fabrication technique allows incorporation of drugs or nutrients into the highly porous structure as demonstrated by the intimate dispersion of fluorescein isothiocyanate (FITC) in the matrix.