A structured and evidence-informed approach to reducing stigma and discrimination associated with mental health conditions. It is grounded in three core principles—leadership by people with lived experience, social contact, and inclusive collaboration—and translates these into a practical four-step process for designing, implementing, and scaling anti-stigma interventions. The toolkit combines conceptual guidance with actionable steps and real-world case studies, enabling adaptation across different policy, service, and community contexts. It also highlights the systemic nature of stigma, including its impact on access to care, social inclusion, and life opportunities, and emphasises the role of coordinated, multisectoral action in addressing these challenge