Sidewalk Sam is the pseudonym of Robert Charles Guillemin (May 4, 1939 – January 26, 2015), a Boston-based artist who resided in Newton, Massachusetts.

Following an accident in 1994 that left him paralyzed, Guillemin increased his focus on large participatory art projects for communities and businesses.

[1] By the early 1980s, Guillemin found business sponsors for his street artworks and shifted to longer-lasting acrylic paints.

[4] After his accident, Guillemin returned to street painting and continued to organize participatory art events in Boston and internationally.

After graduation from Boston University he traveled to Paris and attended courses at the École des Beaux-Arts and the Académie de la Grande Chaumière.