Our evaluation of 16 prominent Agent Oriented Software Engineering (AOSE) methodologies revealed at least two shortcomings in each methodology: Firstly, most are lacking in either agent internal design, agent interaction design and/or agent organization modeling. Secondly, most ignore system extensibility, interoperability and reusability issues. In response to these shortcomings, we synthesize a methodological framework for ontology-centric AOSE which incorporates the key concerns for MAS development and addresses the concerns about reuse and interoperability. The proposed framework is targeted at developing ontology-based multi-agent systems (MAS) in heterogeneous environments and it takes into account ontological commitments of agents throughout the analysis and design processes. The proposed methodological framework can be used in two major ways: as the foundation to build new ontology-centric AOSE methodologies from scratch, or as a repository of add-on methodological elements that can be added to an existing AOSE methodology to enhance it with new support for ontology-based AOSE. In this paper, we demonstrate the former use of the framework through a case study where MOBMAS, a Methodology for Ontology-Based MASs, is built using the proposed framework.