The work presents an account of modern Jerusalem’s demographic evolution and a description of the city’s socio-demographic profile at present. The demographic evolution will be traced back succinctly for about 150 years. The last two decades, since the reunification is treated more intensively. The enormous contrast between the conditions that existed in the mid-19th century at the threshold of modernization, and those prevailing in contemporary Jerusalem, as residents and visitors can experience and study them, should convey an inkling of the progress made. This progress was not achieved by constructing a completely new city – as in the case of Tel-Aviv and many other places in Israel and elsewhere – but by the more intricate processes of reforming a historic and in this instance even a holy city, and developing it through additions of large areas and the innovations of modern life.