The seasonality of the San Miguel Bay, Philippines fishery is discussed in relation to weather patterns and the presence of hills and mountains which shelter different parts of the Bay during the two monsoonal seasons, allowing for year-round fishing. The seasonal nature of fishing a nonetheless, commonly makes necessary a shift from one gear to another to take advantage of the various fishing grounds and fisheries. This in turn affects marketing patterns and the activities of fish processors. Marketing relationships and constraints are related to community size, number of buyers present, and availability of load transportation. The seasonal role of processors is assessed relative to weather conditions, availability of fish, and impact on price levels during seasons of peak supply