Background: Despite the growing importance of social innovation, there is no agreed definition and coherent understanding that facilitates empirical research on this concept. Objective: The present study seeks to provide an integrated and comprehensive definition of social innovation that can help a common and logical understanding of it. Research method: In the research process, under the influence of rational epistemology and in order to link between abstract propositions, analytical-logical method has been used. In this regard, in order to achieve theoretical richness for the final model, at least 116 texts were reviewed and analyzed. Among these texts, 15 books, 3 documents and 32 sites approved by the elites of the seminary, 6 dissertations and 60 articles were analyzed. The extracted propositions were then expertized by fuzzy Delphi method. Findings: In addition to presenting the concept of social innovation, distinguishing social innovation from other concepts of innovation and dissemination and expansion of social innovation, a nine-stage model including: Identifying social needs 2. Ideation and solution development, 3. Evaluation of selected ideas and selection, 4. Establishment and preparation of infrastructure, 5. Implementation of the solution, 6. Creating a feedback loop and impact assessment, 7. Large-scale performance, 8. Institutionalization, 9. Learning and evolution were agreed upon by experts. Conclusion: The study showed that although researchers in recent decades have placed great emphasis on social innovation, but this concept is still much neglected compared to technical innovation. Therefore, in order to discover the coordinates of social innovation, he summarized this concept in a comprehensive set and prevented definite and definite propositions.