Cryopreservation is a collection of methods for freezing living tissues at very low temperatures, usually in liquid nitrogen (LN) (-196oC/-320oF). At these temperatures, living tissues are stable and may be preserved for decades or longer. There are many techniques for protecting living tissues at these very low temperatures and ensuring that they will resume growth when they are thawed. The following slides show some of the methods used in the Plant Research Division to prepare tissues for storage in LN in CREW's Frozen Garden.