While it has been long appreciated that biomechanical forces are involved in bone remodeling and repair, the actual mechanism by which a physical force is translated to the corresponding intracellular signal has largely remained a mystery. To date, most biomechanical research has concentrated upon the effect on bone morphology and architecture, and it is only recently that the complex cellular and molecular pathways involved in this process (called mechanotransduction) are being described. In this paper, we review the current understanding of bone mechanobiology and highlight the implications for clinical medicine and tissue engineering research.