This document discusses sustainability in the construction sector. It begins by defining sustainability and its three pillars - environmental, economic, and social. It then discusses sustainability at various scales from global to local. Sustainable development strategies aim to balance these three pillars through principles like respecting environmental limits and improving quality of life. The construction sector has significant environmental impacts through resource use and pollution, but can also support economic and social sustainability through jobs and infrastructure. Sustainable construction approaches like green building aim to minimize these environmental impacts over the full building lifecycle from construction to demolition.