What punctuation is used to separate three or more items in a series if any items contain commas?

When listing three or more items in a series that themselves contain commas, semicolons serve as the appropriate punctuation to separate the items. This is because semicolons help clarify the boundaries between the items, making it easier for readers to distinguish where one item ends and the next begins. For example, in a series such as "The main dishes included spaghetti, a popular Italian dish; sushi, a traditional Japanese meal; and tacos, a staple of Mexican cuisine," the semicolons prevent confusion that could arise from the internal commas within the items.

Other forms of punctuation, like commas or colons, do not provide the same level of clarity in this situation. Commas could lead to misunderstandings about where one item begins and another ends, while periods typically indicate the end of a sentence or thought, and colons introduce lists rather than separate items within a list. Thus, using semicolons in this context enhances the readability and comprehension of the series.