In experiments previously reported, individual honeybees were trained in a variety of problems to discriminate color-odor compounds. The results could be modeled accurately on the assumption that the associative strength of each component of a compound stimulus changes independently with reinforcement or nonreinforcement of the compound (independence rule) and that the associative strength of a compound is equal to the sum of the strengths of its components (summation rule). In the present experiments, which were designed to challenge the model, honeybees were trained in compound-component problems (choosing between compounds and their separate components) and in conditional problems (choosing between colors on the basis of a common odor or between odors on the basis of a common color). The new data, together with all of the previous data, could be modeled accurately on the further assumption that interaction among the components of a compound generates a new, compound-unique component that gains and loses associative strength in the same way as other components and contributes in the same way to the strength of the compound; the independence and summation rules continue to apply.