Abstract: In the process of advancing social work services through project-based mechanisms, structural contradictions have gradually emerged during the incremental reform of professional development. These contradictions are primarily reflected in the positive internalities and negative externalities of project outcomes. Specifically, professional evaluations demonstrate the positive internalities of an organization’s project professionalism, while the projects simultaneously generate negative externalities that harm the service ecosystem. This structural contradiction stems from the inherent conflict between bureaucratic intervention and professional autonomy, and is expressed through the frictions between “indicator optimization” and “value deviation.” Addressing this dilemma necessitates a professional reconstruction of the service ecosystem. This includes establishing a client-centered evaluation system, aligning project planning with service principles, constructing dual institutional and financial support mechanisms, and fostering a collaborative multi-stakeholder service system.

Key words: social work projects, internality, externality, professional evaluation, service ecosystem