Christina Moore asks, “Should a comma be placed after the last item that comes before the word “and” when listing three or more items in a sentence?”

Unless you are writing for a newspaper or magazine, or for another publication with a style guide that discourages its use, my advice is to use the serial comma.

The main reason for using the serial, or Oxford, comma is that it helps avoid a reader’s momentary confusion. The classic example of this confusion, as noted in World Wide Words, comes from an apocryphal book dedication: “To my parents, Ayn Rand and God.” While we can be pretty sure that the author’s parents are not Ayn Rand and God, the absence of the comma after “Rand” might make the reader pause or re-read.

In her excellent book Rhetorical Grammar, Martha Kolln claims that the absence of a serial comma “may imply a closer connection than actually exists between the last two elements in the series.” She provides an example from The New York Times to demonstrate: “The agricultural and industrial revolutions were accompanied by new plagues, pollutants and weapons of destruction.” In this sentence it’s easy to see how the reader might think that there are two plagues—pollutants and weapons of destruction. A reader might also interpret the last two elements as being shorthand for “pollutants of destruction and weapons of destruction.”

In his poem “Stopping by Woods on a Snowy Evening,” Robert Frost has this terrific line:

These woods are lovely, dark and deep

Here it makes sense to drop the comma before the “and” because Frost is saying that the woods are lovely in that they are dark and deep, rather than saying that the woods are lovely and dark and deep. In other words, the “dark” and “deep” describe the loveliness. Apparently, some poetry anthology editors have added the comma before the “and,” even though Frost didn’t include it in his published version of the poem. Can you see how that comma subtly changes the meaning of the sentence? Those editors should have left the comma out.

Resources

Here are a few other articles and blog posts that discuss the serial comma:

• Discriminations: “The New York Times: A Serial Comma Offender” [link no longer available]
• Capital Community College: “Rules for Comma Usage” [link no longer available]
• World Wide Words: “Oxford Comma”
• Get It Right: “Comma Before ‘and'” provides support from legal references for use of the serial comma