My daughter is 17. She chose to live with her father in June of 2012. Now wants to live with me, August 2013. It's a two year custody agreement. Can we break it somehow?

In June 2012, you went to court and the court ordered that the father have custody for 2 years? I assume that was because she would turn 18.

Whether the court will entertain a modification I can't answer. It would depend on your location, the wording of the agreement, etc. We just don't have enough info to judge. You can try filing for a modification and see what the court says or consult a local attorney who can read the agreement and advise.

If the father will agree, no real issue, but you will have to go back to court and get it modified