Q. In this sentence, “Inside the Bellevue, Washington, laboratory, where innovations are under way . . .” it seems to me that the comma after Washington distracts from the meaning. Since “Bellevue, Washington” describes “laboratory,” could one omit the comma? Or is that a hard, fast, no-exceptions-ever rule?

A. Although we never promote our guidelines as hard, fast, no-exceptions-ever rules, the second comma is Chicago style as well as standard use outside Chicago. The idea is to treat Washington as parenthetical, which requires a pair of commas.