Reviews have been an integral part of software engineering research and practice since their introduction by Fagan. They have been shown to be among the most efficient ways of removing defects in software projects, but previous research has been focused on code or design documents, not on models. Rationale management is considered to be a very effective way of capturing decisions and proposed alternatives. In many projects, however, the process of capturing rationale is only done at the end of the project, or for important milestones. This book introduces IBMR, a method that treats model reviews as a continuous activity, integrating review feedback for models into rationale management, as part of a unified software engineering model. The method reduces review related communication peaks and improves structured externalization of review knowledge for access by all stakeholders.