Programs to promote the electrification of space heating in homes and buildings, primarily using high-efficiency heat pumps, are rapidly growing. Current year budgets are nearly $110 million, up 70% from the prior year. This Topic Brief describes many current electrification programs and policies in detail. As they are early in their evolution, programs are refining their approaches, adjusting their incentives, adding components, and piloting new or complementary approaches such as all-electric new construction.