This Element harnesses new data about gender and sustainability, presents inspiring stories of empowerment, and introduces a framework of building empowerment muscles. It unveils three shocking truths about young women's empowerment as well as disempowerment and patterns of environmental degradation, violence, and exclusion. It presents seven case studies of empowerment from around the world, each matched with distinct skill – a muscle of empowerment. The empowerment muscles are focus, hope, courage, advocacy, solidarity, endurance, and healing. From climate activist Greta Thunberg to the all-girl Afghan robotics team, the #NeverAgain movement against gun violence, to the Hong Kong pro-democracy movement, today's empowered girls are a transformative force for change. Lastly, unlike most works that use empowerment nebulously, this Element concretizes what empowerment is exactly – a set of muscles each reader can build and strengthen through 'workout' training exercises.