Domain-specific architectures, middleware platforms, and analysis techniques leverage domain knowledge to help engineers build systems more effectively. An integrated set of these elements is called a domain-specific development infrastructure (DSDI). DSDIs are commonly created in a costly, ad-hoc fashion because current model-driven engineering (MDE) technologies lack sufficient mechanisms for capturing the semantics of domain concepts. In this paper, we propose a methodology for incorporating semantics within MDE frameworks to simplify and automate DSDI integration. We also present and evaluate a framework, called XTEAM, that implements our approach, resulting in structured processes and enforceable guidelines for DSDI integration. We have applied our approach to several DSDIs, and report on the benefits accrued.