David Robbins told our writing class that when you switch POV, you jar the reader, so you'd better provide them a good payoff - a reward for sticking with you through the jolt and readjustment of getting into a different character's head. So, since I've been thinking about this a lot, Reasons to Switch Viewpoints!
- The current POV character (often the protagonist) cannot be in the right place at the right time for some important event or information. Assuming this isn't simply an instance of having chosen the wrong character for the protagonist, it may be a good time to throw in a section from someone else's viewpoint. You can do this just once at the beginning of the book for setup (think of the Half-Blood Prince chapter that follows the Prime Minister), or pop over to alternate POV a couple of times (think the Voldemort sections in Deathly Hallows - although this is a little different, because it's still sorta-kinda Harry's POV). Some people are critical of the cut-to-what-the-villain's-doing route, but it can be done well, and is certainly better than finding a really contrived way for the protagonist to find out.
- Expanding on this, sometimes you have multiple subplots happening in different places. Brian Jacques' Redwall books do this all the time - the third-person POV is a little distant, so it's not too jarring to have the camera swing over from the Defenders of Redwall to the Traveling Quest Party to the Villain's Camp. David L. Robbins' War of the Rats (which, um, I just realized really sounds like a Redwall book, but I promise it's not) has four firmly-established viewpoints on two sides of the battle of Stalingrad.
- Subplots are collocated, but have seriously different goals or viewpoints. War of the Rats does this, too. The POV characters are two Russians and two Germans. They spend most of the book in the same city, and toward the end the snipers' duel brings them into direct opposition so that switching viewpoints offers intense, and intensely different, takes on the situation.
Furthermore - though this goes without saying when you have well-developed characters - the two Russians' views differ even when they're in the same room, as do those of the two Germans. Seeing the same events unfold through two wildly different filters of values and feelings can be at least as interesting as following characters in different places. (I don't mean you have to go nonlinear in order to literally show the same events - having characters in the same place while the events are happening is enough.) On some level, every character has her own subplot. If Alex and Ben are in one place, even with one presumably shared goal, maybe Alex disagrees with Ben about how to accomplish it. Maybe Alex honestly doesn't care about the goal as much as Ben does. Maybe Alex is secretly in love with Ben. Maybe Alex is planning to poison Ben.
- One character would have the greatest emotional reaction to the events of this scene. This is sort of the psychological version of, "Who's in the right place at the right time?"
Wow, I accidentally covered oodles of stuff in Reason Three. This is the iffiest reason to switch POV, because every single character should be the center of her own subplot, however small or tame, and you simply can't show all of their viewpoints. (Nor would you want to.)
So when do you switch? Well, it's natural to do it when one of the other reasons also applies. What's sometimes tougher, though, is how to do it.
You want to minimize confusion for the reader. Sometimes, this is easy. In Rabbit and Cougar, the chapters alternated POV. (This was basically for Reason Three. The two main characters are two different species from different cultures, and they have different reasons for traveling together and different abilities and opinions - Rabbit doesn't know how to fight, for example, while Cougar can't speak Elven. Toward the end, though, the characters do get separated, so Reason Two comes into it as well.) In Lord of the Dark Downs, though - for the purposes of this edit at least - I don't want to throw in a chapter break for every POV switch. I do use line breaks, which is probably the very minimum heads-up you should give your reader when the POV is changing.
One hopes that every character's voice is distinct enough for readers to know whose head they're in, but realistically, it's not always immediately obvious. I admit, a part of me thought, wouldn't it be cool if they could print these in different colors? Which an e-version could totally do? But of course, the writing should stand alone better than that.
My solution is generally to include a grounding piece in the first paragraph after the line break that makes it obvious whose POV we're in - a sentence that absolutely has to come from that character. Usually, this includes the character's name. It might be, "Cedric found himself, again, the tallest person in the room," or, "Katrina wondered when they would stop for lunch." Later, once the viewpoint is established, I might be more likely to express this sort of sentiment with, "It had to be time for lunch. Wasn't anyone else hungry?"
I'm up for the challenge of rewritey-editing (rewritediting?) Lord of the Dark Downs, but I don't see me writing another seven-viewpoint story. Besides Rabbit and Cougar, all my other long works have one POV each - two in third-person and one in first-person.
Thoughts on point of view? What kind and how many have you used?