This chapter describes the methods of directly quantifying the various processes that produce population change, natality, fertility, mortality, and dispersal. Natality is the number of births, fertility is the number of viable eggs laid by a female, and fecundity is a measure of the total egg production. The measurement of fecundity in various animal groups is reviewed. Stock-recruitment relationships used in fisheries research and the Moron–Ricker curve are described. The analysis of mortality within a generation is discussed, and apparent, real, and indispensable mortality defined. The term ‘dispersal’ covers any movement away from the initial locality, to define neighbourhood dispersal for the process by which individuals migrate into and via adjacent areas, and jump dispersal for longer-distance dispersal where individuals are transported or purposively move quickly to a new area. The determination of the home range or territory of an individual or, for social animals, a colony, is described.