Infixation is characterized by the intrusion of one morphological element inside of another. Since infixes are positioned relative to a phonological “pivot” (e.g., Yu 2007), and since infixes can combine with complex (multimorphemic) stems, it stands to reason that an infix can sometimes, incidentally, appear at a morpheme juncture; and indeed, this is attested. In this talk, I ask: When an infix (incidentally) appears between two morphemes in its stem, does the infix disrupt relations at/across that morpheme juncture that we otherwise expect to be strictly local? I investigate the (non-)transparency of 9 infixes (from 8 languages; 7 language families) that can appear at a morpheme juncture. I find that these infixes disrupt limited types of phonological interactions in their stems, but never interrupt semantic, syntactic, or morphological interactions/relationships in their stems. These findings provide novel evidence for a post-syntactic model of morphology, where exponent choice proceeds from the bottom up, interleaved with some (but not all) phonological processes.