Asymmetric threshold error correction models are used to analyze price relationships and patterns of transmission among farm and retail markets for a variety of dairy products in Spain. Our empirical analysis is conducted using both weekly and monthly price data. Our results suggest that the transmission of shocks is largely unidirectional, running from the farm to retail levels. Formal tests confirm asymmetries, though our results suggest that the effects of these asymmetries are modest. Implications for the organizational structure of Spanish dairy markets are offered.