Nine US states have signed an agreement to promote the adoption of heat pumps, aiming for at least 65% of residential heating, air conditioning, and water-heating shipments to be heat pumps by 2030. The states will collaborate on pursuing federal funding, developing standards, and laying out a plan for widespread electrification of residential buildings. Heat pumps are seen as a key technology for reducing greenhouse gas emissions and transitioning to zero-emissions residential buildings. The agreement also highlights the need for workforce development and contractor training to support the installation of heat pumps.