What is significant in this chapter as bone biology has already been discussed at length in the previous chapter? Owing to the complex nature of bone, the physiological functions that it is capable of needs an in-depth understanding that is provided here. How bone remodelling occurs and the manner in which metabolism is maintained is a very vital aspect not only for craniofacial specialists but for general dentists also. Much has been done after Wolff’s law of transformation (1892). Micro-mechanisms are the flavour of present day scientists and researchers. Mechanotransduction, micro-damage, signal routing and bone regulators are discussed at length. The question of why bone remodels is dealt with as is regional acceleratory phenomenon.