This handbook focuses on parliamentary action to implement the disarmament agenda put forward by UN Secretary-General António Guterres in his 2018 report entitled Securing our Common Future: An Agenda for Disarmament. This agenda includes a set of goals and practical measures across the entire range of disarmament issues, including weapons of mass destruction, outer space, conventional weapons and future weapon technologies. The handbook provides additional background to these disarmament issues, makes connections between disarmament and sustainable development including climate protection, provides examples of effective policies and parliamentary action, and offers recommendations for further parliamentary action. In light of the COVID-19 pandemic, the handbook also includes a focus on disarmament and pandemics.