In response to the accelerated pace of urbanization and the steady rise in global population, a palpable consequence has manifested - a striking surge in CO2 emissions, emerging as the foremost catalyst behind climate change. Concrete, as one of the most widely used materials in the world aside from water, forms the foundational framework of modern society. However, the production of concrete contributes to 8% of anthropogenic carbon emissions. Despite efforts to reduce these emissions through passive strategies like decreasing clinker content, using local resources, and efficient design, the reduction levels have been limited. Consequently, CO2 emissions from the construction sector have peaked post-pandemic. This talk presents an active carbon reduction strategy for sustainable construction to tackle this challenge. This innovative approach transforms concrete into a carbon sink by utilizing CO2 at different stages of the concrete's lifecycle. Initially, CO2 acts as an activator or rheology modifier, improving the fresh properties of concrete. In the middle stages, CO2 serves as a curing agent, enhancing strength and durability through carbonation curing technology. In the later stages, CO2 functions as a surface enhancer, densifying the concrete's outer surface. This strategy also incorporates major urban solid wastes, such as incineration bottom ash, waste glass, and waste concrete, as precursors in the concrete production process.