This chapter highlights the critical role of human behavior in the One Health framework, highlighting the interconnectedness of human, animal, and environmental health. It underscores the limitations of traditional, siloed approaches, presenting the Behavior Change Wheel (BCW) as a structured methodology for designing effective interventions. The BCW, when contextualized within ecological and biosocial frameworks, and utilizing the COM-B model (Capability, Opportunity, Motivation–Behavior), provides a systematic approach to understanding and modifying health-related behaviors. Furthermore, this chapter will advocate that the BCW should be integrated with systems thinking to address the complex, dynamic nature of One Health challenges. By incorporating feedback loops, leverage points, and mental models, a more holistic understanding of these challenges can be achieved. Furthermore, the “socializing One Health” concept emphasizes the importance of social sciences in shaping effective interventions. Future directions should focus on developing integrated frameworks, creating dynamic simulation models, expanding interdisciplinary research, and implementing participatory approaches to enhance One Health outcomes.