Castro volunteers her time with Community Health Partnership (CHP) of Illinois, a not-for-profit organization that provides primary healthcare for over 7,000 Latino migrant and seasonal farm workers and their families. CHP is comprised of 5 clinics in northern and central Illinois. Susana has been a member of the CHP Board of Directors for 14 years, and for the past two years she has served as the Board President. During her tenure, she has seen it grow from a voucher-only program to a direct care delivery model in which the migrant and seasonal farm workers and their families receive primary healthcare services on site.