A proof that a simple compiler correctly uses the static properties in its symbol table is presented. This is done by regarding the target code produced by the compiler as a syntactic variant of a lambda -term. In general, this lambda -term C may not be equal to the semantics S of the source program: they need to equal only when information in the symbol table is valid. Rules of inference for conditional lambda -judgements are presented, and their soundness is proven. These rules are then used to prove the correctness of a simple compiler that relies on a symbol table. The form of the proof suggests that such proofs may be largely mechanizable.>