Assigning Meaning to Proofs - Report by Robert Constable, subtitled `A semantic basis for problem solving environments'. Constable's aim is to use metamathematical results to guide the making of framewroks for constructive logic, as part of the NuPrl project.
The Meanings of Logical Constants - Essay by Gilbert Harman, arguing for Prawitz's approach to the semantics of logic based upon a conceptual role semantics.