One aim of tool integration is designing an integrated development environment that accesses the data/models of different tools and keeps them consistent throughout a project being considered. Present approaches that aim for data integration by specifying (graphically denoted) consistency checking constraints or consistency preserving transformations are restricted to pairs of documents. We present an example that motivates the need for a more general data/model integration approach which is able to integrate an arbitrary number of MOF-compliant models. From a formal point of view this approach is a generalization of the triple graph grammar document integration approach. From a practical point of view it is a proposal how to specify multidirectional declarative model transformations in the context of OMG's model-driven architecture (MDA) development efforts and its request for proposals for a MOF-compliant "query, view, and transformation" (QVT) approach.