Dialog Punctuation


The Basics
  1. Double quotes, not single quotes, are the standard in U.S. English for quoting dialog. 

    "He said he was looking for trashbags," explained Hannibal.
  2. Only use single quotes for quotes-within-quotes. 

    "He said, 'I'm looking for trashbags', and then took off."

    Also note the following in the above examples:
    • Punctuation goes INSIDE the quotes: ( ," ) NOT outside.
    • There is NO space between the punctuation mark and the closing quote. There is a single space AFTER the closing quote. (According to current style guides, double-spaces ANYWHERE are merely a relic of old typesetting guidelines and should not be used.)

  3. Only use ONE punctuation mark at the end of a quote; that is, the following are INCORRECT: 
    "I want trash bags!", Murdock screamed.

"Where are the trash bags?," asked Murdock.
    CORRECTED, they would be: 

    "I want trash bags!" Murdock screamed.

"Where are the trash bags?" asked Murdock.

Specific Examples

Now, let's look at the most common types of sentence structures involving dialog and examine the correct way to punctuate them. The simplest case is when a passage of dialog is simply modified by an opening or ending phrase which identifies the speaker.

INCORRECT examples: 

"I'm looking for some trash bags." Said Murdock.

Face said. "I think there are some in the back of the van."

CORRECTED : 

"I'm looking for some trash bags," said Murdock.
    ("said" is kept lowercase, and a comma is used, NOT a period.) 
Face said, "I think there are some in the back of the van."
In both cases, the entire passage is meant to be read as one sentence, with only a pause between the quote ("I'm looking for some trash bags") and the identification (said Murdock.) Therefore periods are inappropriate, and commas should be used.

The same exact rule as above is followed if the quote contains an exclamation point or a question mark.

INCORRECT examples: 

"Face, can you get me a trashbag?" Asked Murdock.

"Shut up, fool! I'm sick of you and your trashbags!" Complained B.A.

CORRECTED: 
"Face, can you get me a trashbag?" asked Murdock.

"Shut up, fool! I'm sick of you and your trashbags!" complained B.A.

Now, if there is some action which takes place right after or before a character speaks, yet it is NOT directly related to the quote, use a period, not a comma, to separate the clauses. INCORRECT examples: 

Murdock looked upset, "I really wish I could find a trash bag."

"Don't worry, Captain. I'm sure we'll find you one," Hannibal rested a 
reassuring hand on Murdock's shoulder.

CORRECTED: 
Murdock looked upset. "I really wish I could find a trash bag."

"Don't worry, Captain. I'm sure we'll find you one." Hannibal rested a 
reassuring hand on Murdock's shoulder.
In these examples, the non-dialog section stands alone as a complete sentence (Murdock looked upset.) It should therefore not be connected to the quote that follows. ("I really wish I could find a trash bag.") A period is therefore used, NOT a comma.

Here's one that's a little trickier--a passage of interrupted dialog.

INCORRECT: 

"I talked to the Faceman." Said Murdock. "He told me he'd buy some trash bags 
when he went shopping."
This one is also INCORRECT: 

"I talked to the Faceman," said Murdock, "he told me he'd buy some trash bags 
when he went shopping."

The CORRECT way to punctuate this passage would be as follows: 
"I talked to the Faceman," said Murdock. "He told me he'd buy some trash bags when
he went shopping."
The first section ("I talked to the Faceman," said Murdock.) is a complete sentence by itself, and so it should end with a period. The second quote is also a complete sentence, and should begin capitalized.

Now, if the entire passage had been a single sentence, interrupted only by the mention that Murdock is talking, the following would be CORRECT: 

"I talked to the Faceman," said Murdock, "and he told me he'd buy some trash bags 
when he went shopping."

How to tell the difference? Take the quote all by itself without the interruption, and see if you would use a period or a comma at the break. 
"I talked to the Faceman. He told me he'd buy some trash bags when he went 
shopping."
    (Two separate sentences.) 
"I talked to the Faceman, and he told me he'd buy some trash bags when he went
shopping."
    (One sentence.)
Some of the problems that are encountered, especially in this last type of example, stem from writers who are not careful with or don't understand the differences between complete and incomplete sentences.