This chapter outlines the factors affecting financial profitability of energy retrofits. It shows that building age and typology, energy prices and their forecasts, investor strategies and financing as well as the market reaction toward green retrofits all influence profitability. According to estimates of the US Green Building Council, property owners in commercial real estate are estimated to invest almost one trillion USD until 2023 into sustainably retrofitting their existing buildings. Specific measures comprise mainly the improvement of energy efficiency in heating, air conditioning, ventilation as well as windows and lighting systems. The property industry has a specific responsibility in terms of achieving the political climate and energy goals, as it is a main cause of emissions and energy consumption. But energy-efficiency retrofits are not only politically desired and ecologically required.