Rectangles and Circumstance comprises ten songs co-written and performed by Caroline Shaw and Sō Percussion. Shaw and Sō's Eric Cha-Beach and Adam Sliwinski "sourced a group of nineteenth-century poems that shaped its expressive mode [and] ended up using verses by Christina Rosetti, Emily Brontë, Emily Dickinson, Gertrude Stein, and William Blake," says Sliwinski. "The lyrics on this album by members of the band contain wordplay that explores the same profound feelings explored by Blake and Dickinson.” Shaw and Sō co-produced the album with Grammy-winning engineer Jonathan Low (The National, Taylor Swift).