One behavioural description conform

One behavioural description conforms to another if (and only if) any object hat
behavs as described by one also behaves as described by the other (given a mapping
between the two descriptions). A conformance is a relationship between the two
descriptions, accompanied by a justification that includes the mapping between them
and the rationale for the choices made. Refinement and conformance form the basis
of traceability and document the answer to the "why" question: Why is this design
done in this way?[D'Souza&Wills 1999]