The demand for space cooling and, accordingly, room air conditioners sales are soaring, especially in tropical middle income countries. Energy demand for space cooling is expected to triple till 2050. These market dynamics present a challenge from an energy security and a global warming perspective. In parallel, positive effects of air conditioner ownership on human development are becoming increasingly clear. Policymakers and technical cooperation agencies tend to focus either on the phase-in of new technologies or the end-of-life stage, neglecting the phase in between. This report analyses the second hand market of air conditioners in the Philipppines. It focuses on the question when and how to regulate the second hand market to balance energy, climate, resource and social impacts. It analyses prevalent business models, sales, prices, customers as well as energy efficiency and resource use. Several policy options for dealing with the second hand air conditioner market are developed.