Where do I put the period when I'm quoting?

If I quote someone, the quote ends in a period, and I end the sentence with the quote, where do I put the period? Inside the quotation marks or outside the quotation marks? I'm tempted to put a period inside the quotation marks and a period outside the quotation marks, but I know that's wrong (and it also looks stupid).

Update: I use British English rules for quotation marks. I could find advice for American grammar, but not British.

Solution 1:

There is no single set of "British rules" for when you put a full stop inside and when you put it outside the quotation marks. Different British publishers have different rules.

Look at this article from the Guardian, which gives examples of the different rules that different publishers have. One thing the author says is that putting a full stop outside the quotes in the situation you are asking about, when a full sentence is quoted, "makes me shudder." So to keep the Guardian from shuddering, I would advise putting the full stop inside in this case. The Oxford Guide to Style also recommends putting the period inside the quote if you are quoting a complete sentence (except if the quote is a "explanation or specimen", and while they give examples of these, I think this is to some extent a subjective decision).

[But, for example, should the full stop after "makes me shudder" in my sentence above go inside or outside the quote? Some publishers would say outside, because a full sentence isn't being quoted. But I believe others would say inside, because there was a period there in the original quote. I think either decision is fine, as long as you're consistent.]