Cold climate air source heat pumps (ccASHPs) are a critical technology to fulfill residential electrification and decarbonization goals. High efficiency, quality, and cost-competitive heat pumps are a valid home-heating strategy in any climate - often with generous utility incentives to boost demand. But quality products are only useful if they are properly sized and designed to fit the needs of the home. Nuanced ccASHP sizing and design understanding is a rarity among HVAC contractors. Improperly sized equipment is less efficient and provides less comfort for the occupant. Proper sizing for ccASHPs is more complicated than it is for traditional fossil fuel systems, due to their ability to modulate performance across a range of operating conditions. Heat pumps also have a broad range of system design options between ducted, ductless, mini-split, multi-split, and partial load displacement scenarios. This session details an initiative to bring valued and consistent ccASHP sizing and design workforce training to HVAC contractors on behalf of utility programs. The trainings are created and delivered by heat pump manufacturers - through existing training channels - in fulfillment of a training design guide created by NYSERDA.