In recent years we’ve seen increasing interest in the use of ductless air-source heat pumps (or “mini-splits”) for cold climate applications, particularly for space conditioning in low-load houses and for offsetting electric resistance heat or delivered fossil fuels in existing homes. With interest in the technology growing, a relatively small base of experience is available to tap thus far. This session provides an opportunity to learn from two presenters with significant program and technical experience. It comprises two case studies, one focused on the installation of over 1,000 ductless heat pumps in Maine and one focused directly on the measured performance of a single installation in southwestern Vermont.