Elephants may live for > 60 years, so it is obvious that long-term studies are necessary if we are to understand their life histories. Here, I review long-term population studies, most based on individual elephants, to show the wealth of detailed mechanisms that such studies can reveal. This review is biased toward African savanna elephants, a reflection of existing long-term studies on elephants worldwide. Besides life histories, there are 2 aspects of elephant biology that are illuminated by long-term field studies (not necessarily those based on individual elephants). First is knowledge of spatial dynamics of populations that occur in response to environmental change (climatic or anthropogenic), such as density dependence that is associated with the distribution of surface water or responses to specific management decisions, and second is the effects these ecosystem engineers have on habitats, landscapes, other species, and ultimately on ecosystems. I also argue that these long-term data are crucial to inform conservation policies and associated management actions, such as changes in water-pumping strategies, landscape management, and control of elephant populations.