commonpractice

Common practice refers to the set of norms, conventions, and procedures that are widely accepted within a given field and used as the standard basis for behavior, analysis, and decision making. The term is especially common in musicology, where it denotes the common-practice period of Western art music, roughly spanning from about 1650 to 1900. During this era, composers generally adhered to tonal harmony, functional chord progressions (for example, predominant to dominant to tonic), predictable voice leading, regular phrase structure, and standardized forms such as sonata, symphony, and string quartet. The tonal system employed major and minor keys, diatonic scales, and equal temperament, enabling composers to organize music around a central tonal center with conventional cadences that reaffirm it. While individual composers could be highly innovative, most works shared a common set of technical expectations that audience members and performers understood.

Outside music, common practice describes widely observed procedures or customary law: practices established by long-standing usage within professions or institutions, which may or may not be codified in formal rules. In legal or corporate contexts, it can refer to customary behavior recognized by practitioners, courts, or regulators as a baseline standard, though it may be superseded by explicit statutes or contracts.