When 3/4th of growth is purportedly over as a foetus itself, how far reaching should science be in learning about all its aspects? Right from Day Zero (day of fertilization akin to ground zero) to parturition, pre-natal growth is a humungous phenomenon. This chapter has simple but apt illustrations to guide the student about the embryological events that transform the single cell into a complex organism. Such descriptive ontogeny is much needed for the facial surgeons and orthodontists for planning of growth modification and surgery. The ossification of facial bones is concisely given in a table format. Does the tongue really descend? Does the descent of tongue play an important part in maxilla formation? The role of tongue in facial development is also elaborated upon.