It is frequently observed that over the course of the nineteenth century the chromatic scale gradually supplanted the diatonic. 1 In earlier periods, non-diatonic tones were typically understood to derive from diatonic tones: for example, in C major, the pitch class F≥ might be conceptualized variously as the fifth of B, the leading tone of G, or as an inflection of the more fundamental diatonic pitch class FΩ. By the start of the twentieth century, however, the diatonic scale was increasingly viewed as a selection of seven notes from the more fundamental chromatic collection. No longer dependent on diatonic scale for their function and justification, the chromatic notes had become entities in their own right. Broadly speaking, composers approached this new chromatic context in one of two ways. 2 The first, associated with composers like Wagner, Strauss, and the early Schoenberg, de-emphasized scales other than the chromatic. 3 Chord progressions were no longer constrained to lie within diatonic or other scalar regions. Instead, they occurred directly in chromatic space-often by way of semitonal or stepwise voice leading. Melodic activity also became increasingly chromatic, and conformed less frequently to recognizable scales. Chromaticism thus transformed not only the allowable chord progressions, but also the melodies they accompanied.