Parentheses are half moon brackets that enclose additional information within a sentence. Since they are usually used to enclose information that is not necessary to make the sentence work and titles are meant to be succinct they are not usually used in a title. However, there are instances when parentheses are needed in a title. For example, when dates are used, it is beneficial to put them in parentheses to keep them separate from the rest of the title.
Include parentheses in titles to set off dates such as the birth and death year of a person when writing biography or the period a history book covers. For example, Modern China (1912 - 2010).
Use parentheses in titles to add a clause or side-note. The parentheses enclose additional information that could be removed from the title without ing its informational value. Do not add any information to the title that is not necessary or it will become unwieldy.
Replace a "dash" with parentheses in titles where there isn't room for the longer dash. "Em" dashes are used to add a clause and they work well when there is a comma in the clause. However, they take up more room than parentheses.