Defining peak as the climax of discourse, this paper argues that it is important to identify peak in order to get at the overall grammar of a given discourse. The paper presents case studies in which four instances of peak in narrative discourses occur in languages from four different parts of the world. It also illustrates the occurrence of a thematic peak in a discourse in one of these languages. This is followed by a discussion of peak in a procedural discourse and in an expository discourse. Through the case studies, the paper identifies the following ways for marking peak: (1) rhetorical underlining by means of repetition and paraphrase; (2) heightening of vividness by a tense or a person shift; (3) using such devices as rhetorical questions, dialogue, or drama when they have not been present previously in a discourse; (4) changing pace by varying the length of constituent units such as clauses, sentences, or paragraphs; (5) using onomatopoeia; (6) packing the action line by increasing the ratio of verbs to nonverbs; (7) phasing out the usual markers of event line in favor of the more particular sort of markers that are found in peak; (8) phasing out many of the sequence signals and conjunctions that normally provide cohesion to a discourse; and (9) simulating at the peak of one discourse type the features of another. (FL)