Good IT decision making is a highly desirable property that can be furthered by the use of enterprise architecture, an approach to IT management using diagrammatic models. In order to support decision making, the models must be amenable to various kinds of analysis. It is desirable that the models support the sought after analysis effectively since creation of enterprise architecture models often is a demanding task. This paper suggests a framework for enterprise service interoperability analysis and a metamodel containing the information needed to perform the analysis. The paper also illustrates the use of the framework and metamodel in a fictional example.