I was just wondering what the steps are needed to be taken to modify a divorce decree. My girlfriend is looking to change joint custody living with mother to having full custody. Any advice on this would be helpful, thanks :-)

You don't "amend a divorce decree". You file a Motion for Change of Custody.

This is a very expensive procedure. Make sure your attorney is upfront about the financial end of this. My best friend is going through a custody change right and what was supposed to cost$2000 is already up over $10,000. Having just watched my best friend go through this I know a little about it. First off, you can't just change a divorce decree. If she wants to modify a custody agreement she needs reason. Have you done anything to give her reason (it would have to be major, drugs/physical abuse/change in living enviroment).

It's not me personally. I am with my girlfriend, its her ex, we have already retained a lawyer and she advised us that it would not be as expensive as amending the divorce decree.

The major change is the fact that he is a drug addict(currently in rehab for the 5th time) and has no job or driver's license. Has a pending DUI hearing as well

If you have proof that he is a recovering addict (supeona those medical records!) that is reason for a change in custody. It is very hard to terminate all visitation however, it sounds like you have grounds to terminate or for supervised vistation. If he has a pending DUI then you have to make sure he is not driving around with the child. If he comes to pick the child up you are just as responsible as he is for letting him drive around with the child without a license.

She currently has joint primarily living with mother but is going to try and get supervised visitation. We have discussed it between each other and think that it would be in the best interest to at least give him supervised visitation. The 2 girls currently go on Sundays to see him at the rehab clinic(not inside but out to a park) with his mother. Neither one of us will go, she doesn't even want to see him because he was highly abusive to her and still currently says things to the girls about her and I.

We document everything that he says to them and they come back to us telling. She goes the 25th for her first official meeting. We talked to her on the phone yesterday and she said she would draft up a motion for change of custody and mail it to him after our first visit. IF he agrees to it, great if not we file to go to court right away. I informed the lawyer that my girlfriend is afraid he will start calling her phone and harassing her. The lawyer said for either one of us to pick up the phone ONE time and simply say "please stop calling, anything that needs to be discussed can be spoken about through our attorney" and that's that.