Collagen has been used as a substrate for growth of cells derived from skin and cardiovascular tissue. Experimental results reported in the literature suggest that cell differentiation and orientation is enhanced in the presence of collagen. Extensive progress in cultivation of autogenous and allogeneic cells in vitro on collagen has led to advances in the transplantation of cultured materials. The purpose of this paper is to review the literature regarding cell culture on collagen substrates and to analyze the state of knowledge concerning the long-term effects. In the area of skin, long-term replacement of tissue has been studied extensively. Progress in this area has led to the development of technologies that will be used in the future for producing replacements for a wide variety of tissues and organs.