Chondrocytes in growth cartilage undergo proliferation, hypertrophy, and then die by a mechanism that has not been characterised. The aims of the current study were to document the morphology of dying hypertrophic chondrocytes in equine growth cartilage and to establish a culture system in which the isolated chondrocytes can be induced to undergo the same modes of hypertrophy and physiological death seen in growth cartilage in vivo. Growth cartilage from foetal and growing postnatal horses was examined by electron microscopy. Ultrastructural studies of the tissue specimens suggested that the two types of hypertrophic chondrocytes that have previously been described as dark and light cells were dying by different non-apoptotic forms of cell death. Dying hypertrophic dark chondrocytes were characterised by a dark nucleus, and their cytoplasm appeared to undergo extrusion into the extracellular matrix, whereas light chondrocytes appeared to disintegrate within the cell membrane.