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The available literature on the development of the somites, their subdivision into sclerotome, myotome and dermatome, and the available knowledge on chondrification of the sclerotomal mesenchyme have been reviewed. Whether the sclerotome chondrifies because of self-differentiation (so called “spontaneous chondrogenesis” in vitro) or because of inductive interaction with the notochord and spinal cord has been discussed by reviewing, chronologically, the grafting experiments of the 1920’s and 1930’s, the in vivo transplantation and extirpation experiments of the 1940’s and 1950’s and the in vitro studies of the 1950’s,’ 60’s and’ 70’s. The weight of evidence supports a specific inductive role for the notochord and spinal cord whose absence cannot be compensated for in vivo but for which substitutes exist in vitro. The nature of the inductive activity of these tissues was discussed with emphasis on the recent characterization of extracellular matrix products as the inductive agents. Collagen and glycosaminoglycans, both of which are produced by notochord and by ventral portion of spinal cord, can augment the pre-existing bias of the sclerotome for chondrogenesis by increasing the rate at which sclerotome produces cartilage-specific products. How these observations obtained in vitro might relate to in vivo chondrogenesis has been discussed.