Barrington conducts mixed-methods research to examine social network and structural influences on health and health behaviors, with a focus on HIV prevention and care among female sex workers and their male partners, men who have sex with men, and transgender women in Latin America. She has worked in the Dominican Republic since the mid-1990s and also has current projects in Central America and with Latinos in North Carolina. She leads the qualitative component of several impact evaluations of social cash transfer programs and teaches graduate-level courses in qualitative data analysis and global health.