Three-dimensional (3-D) type I collagen cell culture systems composed of reconstituted collagen fibres are able to support short- and long-term growth of various cell types, including cancer cell lines, endothelial cells, endometrial cells, hepatocytes, osteoblasts and fibroblasts and to sustain or even enhance cell differentiation, in vitro. In addition, 3-D culture systems have been successfully used in the investigation of complex biological processes, such as angiogenesis, wound healing, tumour invasion and metastasis. The latter suggested that 3-D culture systems have the potential to simulate cell-cell interactions, which take place in tissues under physiological and pathophysiological conditions. This review focuses on the investigational use of 3-D collagen cell culture systems in bone physiology and the pathophysiology of skeletal metastasis.