This report provides a balanced overview of trends in the numbers of municipal solid waste-to-energy plants around the world, and their impacts on people and the environment, including climate. It outlines key considerations to assist decision makers in developing countries when contemplating thermal waste-to-energy plants as a waste management option, while recognizing that it is important to always reduce, reuse and recycle before relying on incineration. Finally, as with every technology, investment and installation are never the end of the story. Integration within the local socio-economic context as well as long-term monitoring and maintenance are the only way to make technology work for us. This report approaches thermal waste-to-energy plants from a holistic perspective, positing that this knowledge-based outlook will lead to the positive and progressive outcomes for people and communities that help them to thrive.