Chapter 5 explores the implications of the Laryngeal Articulator Model for phonology and the place of voice quality in phonological analysis. The Phonological Potentials Model (PPM) is explained, and synergistic and anti-synergistic relations are mapped in diagrams. Earlier phonological approaches that do not consider the laryngeal articulator are reviewed, while the PPM demonstrates how cooperative lingual-laryngeal activity can be accommodated in phonological analysis. Case studies of languages having lower-vocal-tract contrasts (vocal register, pharyngealization in click languages) give an idea of the network of articulatory relationships that form the grounding of phonological representations. We highlight vocalic-harmony (so-called [ATR]), syllabic, and tense–lax registers in West African, Northeast African and Southeast Asian languages. The case of Southern Wakashan pharyngeal genesis illustrates the role of voice quality in sound change.