Which is correct: "the importance of money for someone" or "the importance of money to someone"?
This link may help to answer your question http://www.talkenglish.com/Grammar/prepositions-of-to-for.aspx. To is used to indicate relationship. The object has a relationship to the subject in its importance, so to is most appropriate. That is, "The importance of an object to a subject". So, in the example: "the importance of money to someone". Note, however, that "the importance of money for someone" may be commonly used, but the former is grammatically correct.