Demography is the study of a group's age and sex structure. This chapter focuses on the life table and its continuous form, known as a hazard or survivorship model. For an extant group it may be possible to obtain information on ages-at-death, although generally it is more common to have census information on the living. Single census life table estimates for anthropological samples are made additionally difficult because growth rates may be unknown. A hazard model generalizes the life table so that age is a continuous variable. Differences in mortality profiles derived from archaeological skeletons that accumulated over time, often several centuries or more, are commonly interpreted as mainly reflecting overall fertility, not mortality. Inaccurate and biased skeletal age estimates, especially for adults, continue to plague paleodemographic work. The chapter deals with a stationary abridged life table.