OBJECTIVE: To describe the methodology used to measure and explain income-related inequalities in health and health care utilization over time in selected Latin American and Caribbean countries. METHODS: Data from nationally representative household surveys in Brazil, Chile, Colombia, Jamaica, Mexico, and Peru were used to analyze income-related inequalities in health status and health care utilization. Health was measured by self-reported health status, physical limitations, and chronic illness when available. Hospitalization, physician, dentist, preventive, curative, and preventive visits were proxies for health care utilization. Household income was a proxy for socioeconomic status except in Peru, which used household expenditures. Concentration indices were calculated before and after standardization for all dependent variables. Standardized concentration indices are also referred to as horizontal inequity index. Decomposition analysis was used to identify the main determinants of inequality in health care utilization. RESULTS: Results of analysis of the evolution of income-related inequality in health and health care utilization in Brazil, Chile, Colombia, Jamaica, Mexico, and Peru are presented in separate articles in this issue. CONCLUSIONS: The methodology used for analysis of equity in all six country research studies attempts not to determine causality but to describe and explain income-related inequalities in health status and health care utilization over time. While this methodology is robust, it is not free of errors. When possible, errors have been identified and corrected.