Embracing the notion of feasibility, this research shows that the world will probably overshoot 1.5°C, largely owing to low institutional capacity. Energy demand reduction and electrification are two options to turn down the heat, and addressing weak institutions is crucial. In the past, climate scenarios have focused on how to curb warming for the lowest economic cost. But cost is only one factor in the overall feasibility of climate mitigation. New research accounts for other dimensions of feasibility, encompassing technology, natural resources, and the capacity of governments to implement mitigation.