The objective of this monograph is to describe differences in tone realization and perception between two major Vietnamese dialects: Hanoian and Saigonese. The monograph contains a thorough overview of the principal background concepts concerning the lexical function of pitch patterns in the language. The core analyses are based on an extensive sample of several thousand instances of tones for each dialect, and they also address possible effects of speaking style, phrasal prominence and coarticulatory dynamism.