MOFLON: a standard-compliant metamodeling framework with graph transformations. The crucial point in Model Driven Architecture (MDA 1) is that software and system development are based on abstract models that are successively transformed into more specific models, ideally resulting in the desired system. To this end, developers must be enabled to model different aspects like structure, behavior, consistency constraints of the system. This results in a variety of related models, which in turn need tool support on the metalevel. However, there is a lack of tools offering uniform support for metamodel definition, analysis, transformation, and integration. In this paper we present the metamodeling framework MOFLON that addresses these issues by bringing together the latest OMG standards with graph transformations and their formal semantics. MOFLON provides a combination of visual and textual notations and offers powerful modularization concepts. Using MOFLON, developers can generate code for specific tools needed to perform the desired modeling tasks.