Whether or not to use a prologue. This is a tricky question. A prologue is pretty much expected in romantic suspense novels, but more and more, other genres are rejecting them. You have to know your genre. Mysteries and thrillers could get away with them, but I don't know the genres enough to say whether or not they’re expected.
Here's a way you can tell if you need a prologue or not. Ask yourself why you decided to start the story there. Is there a way you can add the same information into the story itself through a flashback (or several), dialogue, narration, or some sort of combination of the three? If you remove the prologue and start with chapter one, would the story still make sense? Many writers think readers need to know every little detail about a character. This isn’t true. While it’s a good exercise to interview your character or fill out a questionnaire about him, we shouldn’t learn every single detail on that sheet. That information is so you can portray him in a realistic, 3D manner. Often, beginning writers use prologues to TELL us about the main character’s life up until now. Don’t do that.
The problem with prologues is that many writers don't understand when to use them or how to properly write them. Prologues need to be short. No more than ten pages, but preferably shorter. They need to be fast paced. If a prologue is all introspection, you need to cut it. The purpose of a prologue is to show something that happened in the past. And I mean the past, not ten minutes ago. If there’s not enough time separating the prologue from chapter one, you need to combine the two and break them up with a scene break instead.
If you’re not writing romantic suspenses, thrillers, or mysteries, I’d say you’d be better off not using a prologue and simply incorporating the same information (if it’s necessary) into the story. If your editor or agent believes you need a prologue, she’ll make you add it. However, having one when it’s not so acceptable in your genre could cost you a sale or the agent.
What genre do you write and are prologues acceptable in it?