Advancing gender equality and inclusion in the world of work requires skilled trainers who can translate normative frameworks, evidence, and lived experiences into transformative learning. Across the ILO's tripartite constituents and partner institutions, there is a growing demand for high-quality gender training that not only raises awareness but also strengthens capacities to challenge discriminatory norms, address systemic barriers, and promote behavioural and institutional change. In many organisations - including ministries, public institutions, social partners, UN agencies, development projects, and the private sector - gender training is often conducted by professionals who have deep thematic knowledge but limited exposure to feminist and participatory pedagogical methods. At the same time, the global expansion of gender-responsive policies, due diligence requirements, care-economy reforms, anti-discrimination regulations, and violence and harassment prevention frameworks has increased the need for trainers who can deliver credible, engaging, and context-sensitive learning aligned with ILO standards. The Certification for Gender Trainers in the World of Work, developed and awarded by the ITCILO, responds to this need by establishing a shared professional standard for designing and delivering effective gender training. It builds on decades of ILO experience in capacity development on gender equality, women's empowerment, and social inclusion, and translates this expertise into a competency-based programme that equips learners to facilitate transformative processes rather than one-off awareness sessions.