What do I need to do to move my child out of state?

You can certainly move the child out of state, however, you should inform the other parent of this new circumstances and reassure him that this move will not be able to affect his parental rights. If he still does not cooperate then you should get a lawyer that would be able to help you get permission from the court. To me personally, I consider this to be an easy modification but you should work with a an attorney to ensure that everything goes smoothly. If as parents you both can agree on the move, you guys can very well close out the custody case and focus on starting a new life in both MA and NY. Once you do move to NY, and if ever there is a dispute, you guys can always start the case again in NY where the kids will be residing. There is a lot that can happen and I can not play out all the possible scenario in this question-answer forum. Please consult a lawyer in a private consultation, phone or in person and go over all your available options.   Above answer and comments to questions are for general purposes only and does not constitute legal advice or establishes an attorney-client relationship without a signed retainer. Please reach out to an attorney you are comfortable with working and discussing your case in more details.