Using individual-level data from the 2000 Mexican Survey of Satisfaction with Health Services we estimate a two-part negative binomial hurdle model to evaluate the decision-making process of health care utilization in Mexico. We find that there are income-related differences in utilization associated with the first visit to a physician, as well as substantial utilization differences by region, employment, insurance and financial status. There are also income-related differences in the first visit to a specialist but not in the number of days hospitalized. The results suggest that increasing initial access to services via income and insurance coverage and providing financial resources to underserved regions can substantially improve access to care and, ultimately, population health.