How to write dialogue

Dialogue is, at its simplest, conversation between two or more characters on the page. Wikipedia's article on dialogue in writing defines it in exactly those words and marks the boundary case: if there is only one character talking, it is a monologue. The word carries a longer history than the novel, though. Wikipedia's main article on dialogue describes it as "an interactive communication between two or more people, and a literary and theatrical form that depicts such an exchange", a form associated in the West chiefly with Plato's Socratic dialogues and used as an independent literary form since antiquity. Fiction borrowed a working tool from that tradition: people revealed through what they say to each other.

What dialogue does on the page

Craft consensus assigns dialogue three jobs, and good lines do them together. It characterizes: Janet Burroway's writing handbook, quoted in the Wikipedia article, calls dialogue "a direct basic method of character presentation", and the article adds that it makes characters "more believable to the reader, by allowing them to voice their internal thoughts". It advances the story: conversation is where characters want things from each other, and wanting is plot. And it raises tension: two people in a room saying not quite what they mean is a pressure vessel, and the reader stays for the pop.

The third job is the one most often forgotten. A scene where everyone says exactly what they mean, and gets it, has nothing to hold it; the gap between what is said and what is wanted is where the scene breathes.

The functional test: every line earns its place

The novelist William Sloane, quoted in the same Wikipedia article, set the standard most cleanly: "It must do more than one thing at a time or it is too inert for the purposes of fiction." That is the whole audit. Take any line and ask what it is doing. Is it characterizing the speaker? Changing what somebody knows or wants? Adding pressure? A line doing none of these is inert, and inert dialogue is the spoken cousin of a told emotion (the same show, don't tell logic: a quarrel about the dishes shows a marriage failing without announcing it).

Not every exchange needs the full treatment. The article notes dialogue can be "summarized as part of the narrative or written as indirect speech": greetings, logistics and low-stakes filler are better summarized, precisely so the dramatized exchanges stand out.

Differentiating voices

A reader should be able to cover the tags and still know who is talking. Each speaker needs diction, rhythm and habit of their own: vocabulary that fits their education and world, sentences that run long or clip short, evasions and verbal tics that belong to them alone. Voice here is continuous with the rest of the prose. In close third, the narration itself soaks up the viewpoint character's voice (that mechanism is free indirect discourse), and how much interiority any speaker gets is fixed by your point of view scheme before the scene starts. Voice bleed, where everyone sounds like the author, is the failure to check for first.

Tags and beats

On the page, dialogue "is usually identified by the use of quotation marks and a dialogue tag, such as 'she said'", per the Wikipedia article, which also lists the tag's other names: identifier, attributive, speaker attribution, tag line. The craft consensus on tags is boring and correct: said and asked are invisible, and Stephen King "asserted that said is the best dialogue tag to use". The flashier verbs called said-bookisms (murmured, thundered and their relatives) are thought to "detract from the narrative if over-used", and Cory Doctorow calls them "writerly laziness" that "weakens the story".

The alternative to a tag is a beat: a small physical action in the same paragraph that attributes the line while keeping the scene visible. She set down the fork. He looked at the window. Beats carry attribution and characterization at once, which passes the functional test twice. One caution from the other side of the page: reaction shots during dialogue are where mid-scene viewpoint slips cluster, so check whose head each beat is filmed from (see head-hopping).

Subtext

Characters, like people, rarely say the thing. They deflect with jokes, answer a different question, discuss the dishes while the marriage is the subject. Subtext is the meaning traveling under the spoken line, and dialogue is where it does its best work, because the reader hears the surface and watches the gap. It runs directly on what a character is hiding: a speaker with a secret turns every exchange into a negotiation between concealment and slip, and the discipline of deciding who knows what, and when it comes out (see character secrets and reveals), is what keeps subtext controlled instead of vague.

Dialogue in web fiction

Dialogue-heavy chapters read fast. Short paragraphs, white space, phone screens: a serial reader scrolling on a commute gets through a talky installment with less friction, which is one reason so many successful web serials run talky. The caveat cuts the other way: a chapter that is only voices floats free of its scene. Percy Lubbock's old observation, quoted in the Wikipedia article, still holds: the novelist must interpose "on his own account to let us know how the people appeared", because bare dialogue reads like a play. Ground the lines in a setting now and then, and check the chapter's shape against its length target.

A revision pass for dialogue is cheap and high-yield: read the exchanges aloud, cut every inert line, demote low-stakes exchanges to summary, and confirm each speaker still sounds like themselves with the tags covered. The lines that survive will be doing several jobs at once, which is what Sloane's test asked for all along.