I review evidence of three kinds relating to leakages in modularity within language domains and between linguistic and nonlinguistic action. One kind of evidence shows that the form-meaning “rift” in language that enables the important principle of duality of patterning and the particulate principle of self-diversifying systems is bridged in many ways. Segmental language forms have iconic meanings, and form-meaning correlations of other kinds emerge cross linguistically. A second kind of evidence occurs in parallel transmission of linguistic prosodic information with iconic and emotional information conveyed suprasegmentally. The final kind of evidence shows the integrality of linguistic and nonlinguistic action (deictic points, speech-accompanying gestures, head motions, facial expressions, etc) in conveying communicative information in public language use. I suggest that these violations of modularity within language and between linguistic and nonlinguistic action reflect the dynamic effects of sets of competing and cooperating constraints including, among others, parity and learnability of language forms that shape communicative actions in social activity.