In this talk, I propose a hypothesis which holds that speakers possess knowledge of articulatory distance between a target sound and other sounds. It is dubbed the POA-map hypothesis (for ‘place of articulation’) here. We look at two cases involving the POA-map: Japanese velar fronting and Hawaiian consonantal adaptation. The most important conclusion drawn here is that the POA-map is part of phonological UG available to language learners and loanword adapters.