Our studies of the regeneration of interfacial adhesion in micro-composites have shown that fiber/thermoplastic (aramid/polycarbonate) bonds can be completely regenerated, the degree of regeneration depending on both time and temperature of heating. Complete regeneration requires high temperatures, suggesting that mechanical interlocking resulting from flow of heat-softened resin into fiber surface crevices may be the primary mechanism of bond strength regeneration. Only partial regeneration of fiber/thermosetting resin (epoxy with aramid and carbon fibers) bond strength has been achieved, and this appears to be independent of fiber and reheating time. Apparently, the viscoelastic behavior of the resin is a critical factor in bond strength regeneration.