This paper addresses the verification of protocol conformance between two types of state machines in
model-driven software design: protocol state machines that enable specifying allowed sequences of signals and behavioral
state machines that are intended for implementation specification. The contribution of the present paper, is to provide
a methodology, which is based on refinement mappings, to automatically verify on protocol conformance. It helps to turn
UML into a powerful and interesting tool for the development of business critical software systems.