In this paper I have argued that the theory of relevance provides a general account of the interpretation of metaphor and metonymy as well as that of non-metaphorical utterances, and I have criticised the Gricean approach to metaphor which is based on the priority of literal interpretation. Interpretations of metaphor and metonymy usually involve some indirectness. I have attempted to shed light on the process in which the extra processing effort incurred by the indirectness is offset by effects. Metaphor and metonymy both function not only to indicate that the hearer is expected to take a large responsibility in searching for contextual effect but also in limiting the directions in which the processing may proceed. (Nam Sun Song)