Book excerpt: Modeling as used in social science and in particular in de­mography, is a complicated process. Modeling population dynamics has traditionally been the central branch of mathematical biology, and counts more than 210 years of history, notwithstanding the recent expansion of this sci­ence's scope. The first principle of population dynamics is widely regarded as the exponential law of Malthus, as modeled by the Malthusian growth model. The early period was dominated by de­mographic studies such as the work of Benjamin Gompertz and Pierre François Verhulst in the early 19th century, who refined and adjusted the Malthusian demographic model. In this volume, dedicated to the 250th anniversary of Thomas R. Malthus, we publish seve­ral modern analyses that illustrate the honored place the Malthus's work occupies in the science of demographic modeling. Editors: Maxime Seveleu-Dubrovnik and William R. Nelson