The grammar question I get asked more than any other: Is there a comma between the last item in a series and the word “and”? In other words, is it “potatoes, artichokes, and radishes” or “potatoes, artichokes and radishes”? My answer is always the same: It depends who you ask. The Associated Press Stylebook, The New York Times Manual of Style and Usage, and many other stylebooks used by newspapers and magazines suggest forgoing that last comma unless doing so would cause confusion on the part of the reader.
Strunk and White, in their classic Elements of Style, say to always always always use the serial comma to avoid ambiguity: “use a comma after each term,” no ifs, ands, or buts, they declare. The Chicago Manual of Style, the United States Government Printing Office’s Style Manual, and Fowler’s Dictionary of Modern English Usage agree. Here’s my advice: Unless your client requires you to slavishly follow AP style, use the comma. It can’t hurt, after all, and it will avoid uncertainty. Just ask my parents, Elaine and Seymour.
Note: Despite the AP and NYT rule stated here, I really don’t understand why people refrain from using a comma before the last item in a series. It’s not exactly keeping me up nights - to be honest, issues of grammar never prevent me from sleeping - but since there’s nothing wrong with using it, and it always clears up any confusion, why not just use it?