To Have and Have Not is a 1937 novel by Ernest Hemingway (July 21, 1899 - July 2, 1961) about Harry Morgan, a fishing boat captain who runs contraband between Cuba and Florida. The novel depicts Harry as an essentially good man who is forced into blackmarket activity by economic forces beyond his control. Initially, his fishing charter customer Mr. Johnson tricks Harry by slipping away without paying any of the money he owes him. Johnson then flees back to the mainland by airplane before Harry realizes what has happened. Harry then makes a critical decision to smuggle Chinese immigrants into Florida in order to feed his family. (He kills the person in charge of getting the immigrants to Florida because the man "Obviously was far too easily persuaded to pay him more for the transport".) The Great Depression features prominently in the novel, forcing depravity and hunger on the poor residents of Key West who are referred to as "Conchs".

The novel consists of two earlier short stories, "One Trip Across" and "The Tradesmans Return", which make up the opening chapters and a novella, written later, which makes up two-thirds of the book) . The style is distinctly modernistic with the narrative being told from multiple viewpoints at different times by different characters. It begins in first person (Harrys viewpoint), moves to third person omniscient, then back to first person (Als viewpoint), then back to first person (Harrys again), then back to third person omniscient where it stays for the rest of the novel. As a result, names of characters are frequently supplied under the chapter headings to indicate who is narrating that section of the novel.

Legend has it that Hemingway wrote the book as part of a contractual obligation and hated it. Howard Hawks, who adapted the novel for film claimed that Hemingway had told him it was his worst book, and a "bunch of junk". It is also claimed that he wrote the book at the Compleat Angler Hotel on Bimini, in the Bahamas.