This thesis shows how to make use of the intensional information relating specifications to implementations. It views the proofs of properties of specifications as identifying the intensional parts of implementations relevant to the property. It provides a concrete instance of such proofs by adopting labelled transition systems, modal-mu calculus and the tableau methods of Stirling and Bradfield as a framework for generating intensional information. The intensional information generated from proofs about models of systems can be used to verify behaviours of implementations of systems. By annotating implementations of systems with the atomic actions of their models we can apply oracle technique to verifying implementation behaviour. The extra richness of intensional information allows oracles derived from proofs, rather than just from properties, to be much more discriminating of failures in the implementation. The emphasis of oracle-based testing and verification is on practical improvements in the quality of distributed systems. Therefore the intensional idea is developed into a framework for a practical system. Case study systems are examined to identify where system developers can be helped by computerised systems to integrate auditioning into the software development process.