Acres of Skin: Human Experiments at Holmesburg Prison is a 1998 book by Allen Hornblum. The book documents clinical non-therapeutic medical experiments on prison inmates at Holmesburg Prison in Philadelphia from 1951 to 1974, conducted under the direction of dermatologist Albert Kligman. The title of the book is a reference to Kligman's reaction on seeing hundreds of prisoners when he entered the prison: "All I saw before me were acres of skin" ... "It was like a farmer seeing a fertile field for the first time".