PROJECT SUMMARY This project will measure how exposures to climatic variability (i.e., temperature and precipitation anomalies) during early-life and adolescence affect the fertility, health, migration, and socioeconomic statuses of working- age adults. We use data from the Indonesian and Mexican Family Life Surveys to measure women’s fertility (children ever born) and adults’ lifetime migration, body mass index, education, and consumption expenditures among 15-49 year-old individuals in Indonesia (~115,000 observations from 51,000 individuals) and Mexico (~60,000 observations from 41,000 individuals). We then link these demographic records to high-resolution climate data, and measure individuals’ climate exposures during early childhood (ages -1 to 4) and adolescence (ages 9 to 14). We fit a series of country-specific regression models that measure the effects of climate exposures during each critical period on the focal outcomes, controlling for individual characteristics and both birthplace and birth-year fixed effects. We then evaluate whether and how climate effects differ by individuals’ age, sex, parental education, parental mortality, and rural (or urban) residence at birth. The third analyses compare the effects of early-life and adolescent shocks with the impacts of contemporaneous shocks that occurred just prior to when the focal outcomes were measured. These analyses also account for the potential compounding or accumulation of impacts from repeated shocks. Our main analyses are complemented by a series of robustness checks. Overall, we provide new insights into the links between climate change and working-age adults’ wellbeing in middle-income, developing contexts.