In recent years, music theorists and cognitive psychologists have agreed that hierarchical organizations are an effective means of describing structural and perceptual aspects of music. This article proposes that any hierarchical theory should be limited because the amount of information humans are able to take in and process is limited, as is well known in the cognitive field. When music is perceived according to Gestalt principles, the limit of organization will be three or four musical events on a level. When music perception is aided by cultural experience, this number of events may be exceeded by grouping the events into processing units called musical constituents. In this way, the hierarchical theory accounts for both the abstract and cultural aspects of musical experience. The notion of structural limits explains why the hierarchical model has been so persuasive and, by the use of three examples, shows how it can be a useful perspective for musical analysis.