This article documents beliefs among Hispanic immigrant and migrant families in central Washington State about the etiology, symptomology, and appropriate treatments for illnesses experienced by their young children. Similar information was gathered from health care staff at several area biomedical facilities. We integrate data from the childhood health project and the authors' previous research to refine the ethnomedical knowledge base and assumptions about the impact of migration histories and acculturative forces on Hispanic health belief systems and therapeutic decision-making. The analysis is situated in the region's political economic context, dominated by agribusiness, which reveals the enmeshed structural forces that influence the children's health care. We conclude that only when cultural and structural factors are considered in concert can these approaches most effectively contribute to understanding family responses to childhood illness at local community levels as well as at broader analytic scales, and to the development of culturally relevant and effective health care.