It is well known that a building's energy performance (heating and artificial lighting) and the comfort of occupants are very strongly correlated with a building envelope’s access to the sun and its ability to harness that resource. We need to determine how the climate interacts with the built environment, how buildings influence each other, and how the indoor environment is impacted by these. In addition, in order to achieve any objectives related to sustainability, it is far more effective to influence building design in its early phases than in its final ones. This presentation will provide an overview of how the combination of climate science, statistics, lighting and thermal analysis on optimizing the form of the built environment – from building massing to the specifics of façade technologies – can bring promising answers if properly translated into design recommendations and guidance.