Cryopreservation is the technique in which very low temperatures to preserve structurally intact living cells and tissues. Different modes of preservation are used for the preservation of hematopoietic, mesenchymal and human embryonic stem cells. The cryopreservation protocol for a given cell type requires specification of (1) pre-freeze processing; (2) introduction of a cryopreservation solution; (3) freezing protocol; (4) storage conditions; (5) thawing conditions and (6) post-thaw assessment. Vitrification is a cryopreservation technique that leads to a glass-like solidification. Human embryonic stem cells (hESC's) can be preserved by this technique.