In this paper we set up, estimate and test a short-run model for the poultry sector in Greece. The model allows for the simultaneous existence of a monopolistically competitive and a competitive segment, and determines producer and consumer prices, and the quantity consumed. We provide evidence on steady-state parameters such as demand and supply elasticities, as well as on speeds of adjustment of prices and quantities. The evidence suggests that adjustment is very rapid, although quantities appear to be adjusting more quickly than prices. The model is used to examine the dynamics of adjustment to demand and supply-side disturbances.