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Three pigeons served respectively in three experiments in which the effects of within-session alternative food combined conjointly or concurrently with variable-interval or fixed-ratio schedules of reinforcement in defining the economic continuum were examined. In Experiment 1, the frequency of alternative food was varied in an otherwise closed economy. As the frequency of the alternative food decreased, the rate of responding declined. In Experiments 2 and 3 alternative foods were combined, respectively, with variable-interval and fixed-ratio schedules, in open and closed economies. Generally, response rates were higher in the open than in the closed economies (an economic effect), although the alternative food delivery reduced the rates of responding (a schedule effect). Response patterning was unique under the different economic contexts in each experiment, showing bouts of responding and pausing in closed economies with variable-interval alternatives, low, consistent responding in open and closed economies with variable-time alternatives, and single periods of responding in open economies with variable-interval alternatives. The results illustrate the complexity of the interaction of economic and schedule variables in defining the economic continuum, and suggest an important role for within-session alternative food.