For any phonotactic restriction on syllable onsets and codas, it can be shown that parallel restrictions are attested at edges of each higher prosodic domain. Onsets can be required at the beginnings of syllables, words, or utterances; codas can be banned at the ends of any of these constituents; and so on. This paper argues that these restrictions follow from constraint schemata: any markedness constraint on syllable onsets or codas (M Ons or M Coda ) is part of a family of constraints (M Ons (Onset/PCat) or M Coda (Coda/PCat)) imposing parallel restrictions on initial onsets or final codas of each prosodic domain. These prosodic domain-edge markedness constraints can induce epenthesis, deletion, or other segmental changes at domain edges; they can also shape words' prosodic structures.