This article investigates interactions between the scope of QPs and the restrictions imposed by binding theory. It presents new evidence that Condition C applies at (and only at) LF and demonstrates that this condition can serve as a powerful tool for distinguishing among various claims regarding the nature of LF and the inventory of semantic mechanisms. The conclusions reached are these: (1) Scope reconstruction is represented in the syntax (semantic type-shifting operations are very limited). (2) Ā-chains have the following properties: (a) Scope reconstruction results from deleting the head of the chain and interpreting a copy at the tail. (b) Non-scope-reconstruction results from interpreting the head of the chain with a copy of the restrictor at the tail (unless this option is impossible, as in antecedent-contained deletion, in which case the copy is changed to a variable as in standard notations). (c) VP adjunction is an intermediate landing site. (3) A-chains are different in a way that at the moment requires a stipulative distinction.