 Macrophages are important immune cells that are involved in the foreign body reaction after biomaterial implantation. They are able to recognize and engulf foreign material, as well as initiate the inflammatory process. Physicochemical cues on the biomaterial surface can influence the behavior of macrophages, such as adherence and fusion into giant cells. Understanding these interactions can help us develop new biomaterials that elicit a favorable immune response and perform for their intended applications. This article was authored by Sishan Sheikh, Patricia J. Brooks, Borya Barzaleh, and others.