The proofreader is an unexpected jack-of-all-trades. During the final phase of editing, a proofreader verifies that a document is sound before it is published. Yes, they do check spelling, grammar, and punctuation, but they also ensure that the format of the document is correct, that percentages and numbers appear consistently and adhere to house style. They make sure that the layout all graphs and tables are laid out correctly, and that the document contains all appropriate components, such as preliminary matter (dedications, copyright page, etc.) and end matter. The proofreader is the roadblock between the document and publication, and for this reason, multiple proofreads by multiple proofreaders should be conducted (NY Book Editors).