Aspects of the present disclosure relate to modular wall systems, modular wall units, and methods of installing modular wall systems for indoor environments such as medical treatment environments, In one implementation, a first outer panel and a second outer panel are spaced apart from each other to form a window, and a front panel is attached to front surfaces of the first and second outer panels. The front panel is formed of a polymeric material or a composite material, and the front panel includes an aesthetic design thereon.