The 4th International Parliamentarians’ Conference on the promotion of Freedom of Religion or Belief (FoRB) will be held from Monday the 1st of May 2023 to Thursday 4th May 2023 in Nairobi- Kenya. The Conference theme, Leave No One Behind, is the central, transformative promise of the UN 2030 Agenda for Sustainable Development and its Sustainable Development Goals (SDG). It represents the unequivocal commitment of all UN Member States to eradicate poverty in all its forms, end discrimination and exclusion, and to reduce the inequalities and vulnerabilities that leave people behind and undermine the potential of individuals and of humanity. By linking FoRB to the SDG agenda, the Conference makes the case that in many instances a major cause of people being left behind is persistent forms of discrimination on the grounds of religion or belief, which leaves individuals, families and whole communities marginalized and excluded. Addressing such inequalities and discrimination, as well as their root causes, can contribute to human flourishing as well as just, peaceful and inclusive societies. Parliamentarians have a critical role in advancing this joint agenda not only as lawmakers, but also in setting budgets and providing the necessary oversight. No country can fulfill its potential if its people are denied the freedom to hold, to change and to profess their innermost beliefs. With less than ten years left to achieve the SDGs, world leaders at the SDG Summit in September 2019 called for a Decade of Action to deliver on these Goals.