Abstract: Provided herein are systems, methods, and cryoprotective solutions for reversible cryopreservation of biological specimens, whole organs, and whole organisms. Exemplary methods include loading a cryoprotective agent into the biological specimen, cooling the biological specimen to a cryogenic temperature for preservation, storing the biological specimen at a preservation temperature state to preserve the biological specimen, rewarming the biological specimen by increasing a temperature of the biological specimen above the preservation temperature state, and unloading the cryoprotective agent from the biological specimen. The cooling is performed at a first rate to reduce ice formation, substantially homogeneously to reduce propensity for cracking of the preserved biological specimen, and at a first pressure to prevent or reduce ice expansion within the preserved biological specimen.