Very well-researched and well-written, this book provides an excellent discussion of the activities of federal surveillance agencies in the Pittsburgh mill district (western Pennsylvania, northern West Virginia, and eastern Ohio). However, Seeing Reds is neither about surveillance agencies nor the Pittsburgh Left per se, but rather about their intersection: the “federal government's effort to define, understand, and suppress leftists” during the period of World War One. It begins with an excellent survey of the early history of federal surveillance agencies, including the Bureau of Investigation (BI), the Office of Naval Intelligence, the Military Intelligence Division, and the American Protective League. McCormick pays special attention to the BI, the original name of the Federal Bureau of Investigation. He looks closely at four men who, as special agents in the Pittsburgh Field Office, played a particularly important part in his story. Each had a background in either police and/or private investigative work or a college degree and/or legal training.