Author is usually consulted at this point. When agent is happy, contract is sent to author. Author queries agent if anything not understood. Agent deducts commission and expenses, if any, sends check to author. Non-fiction author writes book.
Editorial process begins for fiction author who has already written book.
Author delivers on time. Queries are sent to author. Sometimes publisher solicits great quotes for book jacket. Editor reviews and, if corrections, inputs onto disk. Publisher decides, based on advance sales, advance paid, etc., how many to print.