Mortality and recruitment rates are fundamental measures of population dynamics. Researchers have defined and estimated these vital rates in various ways. All these measures are influenced by the structure, or the demographic heterogeneity of a target population in two ways: (i) When relative abundance of subpopulations is unchanged, estimates of vital rates that assume homogeneity are increasingly dominated by the demographic properties of the subpopulations with the lowest vital rates, as census intervals are extended (Sheil & May 1996); (ii) when net growth rates vary among subpopulations, vital rate estimates are biased towards those in the least changing subpopulation with extended census time. So far, only an empirical correction of the bias due to census intervals has been employed (Lewis et al. 2004). We describe a novel estimation procedure that explicitly accounts for demographic heterogeneity among subpopulations such as species and sites.