What did Sherman Alexie contribute to the nonfiction book, Heart Berries?

Sherman Alexie is one of Terese's professors at the Institute of American Indian Arts where she did her M.F.A. He is also the author of the book's introduction. Alexie is a well-known and highly lauded figure in the Native American literary scene and thus in endorsement of her talent and her work carries significant weight. By penning the book's introduction, Alexie places Terese's work in the context and canon of contemporary indigenous literature while also giving it advance praise. This advance praise has the potential to frame the reader's experience of the book as their opinions may be shaped by those of a respected authority like Alexie.