Critic Irving Sandler (writing in Art in America, January 2005) has noted that Gummer's work is recognizably rooted in constructivism, but also writes that "in extending and deflecting Constructivist art in a new direction, Gummer has rendered it peculiarly contemporary."

Sandler also writes that Gummer's works "give postmodern life to classic principles of abstract composition.

Since then, his works have been featured at two dozen solo shows at museums and galleries around the East Coast and Midwest.

[5] Gummer's commissioned works have included Primary Compass (2000), a site-specific outdoor permanent sculpture at the Butler Institute of American Art,[6] Youngstown, Ohio, and a sculpture/fountain in Historic New Harmony, New Harmony, Indiana.

One stainless steel and stained glass sculpture, Southern Circle, standing 25 feet (7.6 m) tall and weighing approximately 20,000 pounds, was commissioned by the city of Indianapolis and dedicated in October, 2004.

"Primary Separation", a permanent installation at the Massachusetts Museum of Contemporary Art, was completed in 2006.