Living bone has the ability to adapt its structure to a changing mechanical environment. This is possible since bone is continuously formed and resorbed by cells during the mechano‐regulated process of bone (re)modelling. This chapter aims to review the joint effort of different scientific communities, who address the problem of bone adaptation on very different length and time scales. The bioengineer asks the question of what is the actual mechanical load in our bones, which is surprisingly challenging even on the macroscopic scale, whereas the (molecular) biologist searches for the basis of the regulation on the inter‐ and intracellular level. Experiments are performed on animals and using computer models to understand the mechano‐regulation of bone's structural adaptation in a more systemic way. To learn from the bony fossil record about living habits, anthropologists try to interpret bone structures in terms of their loading conditions during life. Last but not least, bone serves as a source of inspiration for the materials scientist developing synthetic adaptive materials.