The economic crisis at the beginning of the eighties had an impact on the 20 th -century Costa Rica in many different ways. Government programs were successful in reducing the proportion of poor people from a 35% in 1985 to a 23% in 2000. This article utilizes official household surveys corresponding to the period 1981-2002 and population census to perform an estimation of age, cohort and period effects, in order to show that poverty among the elderly can be understood as a cohort effect. Their poverty conditions are associated with their low schooling, mainly among men. The probability of having the right to a retirement pension and the fact that the people with lower educational level got low income during their late working years, mediate in the relationship between schooling and poverty as a cohort effect.