In many Romance languages, negative expressions exhibit a robust distributional asymmetry.When in post-verbal positions, they require theco-presence of negation; when in pre-verbal positions,they are incompatible with it. In the same languages, bare nominals exhibit a distribution that parallels the negativeone in some striking respects. They are possible in post-verbal positions, but infelicitous as pre-verbal subjects. Similar distributionalparallelisms between these expressions are shown toobtain cross-linguistically and diachronically and are argued to derive from their common internal syntactic and semantics properties. Both expressions have a 'deficient' DP, lack quantificational force, and are unable to check the D feature of EPP. Bare nominals may lack D0, but negative expressions contain a null D0syntactically licensed under DP internal Spec Headagreement or head movement. As these operations result from parametricoptions in DP syntax and have consequences on the semantic nature of these expressions, the central result of the paper isto derive cross-linguistic variations in negative concord from independentchoices in DP syntax.