Today, clay bricks are facing technological challenges and are uncompetitive compared to materials such as concrete. Their performance must be improved if they are to stand up to the competition. Increasing environmental concerns over the accumulation of unmanaged wastes from agricultural or industrial productions have made these good candidates for incorporation into building materials to improve their performance. This process leads to the formation of pores in the bricks, producing lightweight and sustainable building materials.This paper reviews the different pore-forming agents from renewable or mineral resources as described in the literature. It also presents the impact of pore-forming agents on the physical, mechanical and thermal properties of clay bricks.