When using fonts in your ads be careful, ads can get cluttered and difficult to read if too many fonts are used or the wrong ones are chosen. Try to keep the number of fonts you use on any one ad down to three. A serif (which can include script fonts), sans serif  and a stand out font for drop caps, asides and other calls to action.

There are some occasions where more fonts are appropriate  and especially if variations of the same font are being used. But there ARE just some projects that need more than 2 or 3 fonts. 🙂