Courts respect the fundamental right of a parent to raise and make decisions for his children, thus taking custody of a child from her natural parent is only possible in very limited circumstances. This includes situations such as where a parent has been adjudicated unfit, has been incarcerated for an extended period or has committed domestic violence, abuse or neglect of a child. In these situations, you can file a petition for custody in the appropriate court, where the court will evaluate the petition to determine if a change of custody is in the child's best interest.
Draft your petition. You can obtain a blank copy of the petition form from your local courthouse's office of the clerk. If there has been a previous custody or guardianship case, use that caption for your motion, otherwise the clerk will assign your petition a case number when you file. If you believe there is an emergency basis for your petition, you can use the emergency petition for custody form.
While specifics of form vary by jurisdiction, you will need to include detailed information on the child, the parents, any guardians, along with your financial information. In addition, include a copy of the current custody order (if one exists). Input into the narrative your request for custody, and provide a brief explanation of your basis for making the request. You should bring at least two copies of the petition, as some courts require up to six copies to be filed with the original, though these courts usually provide paid access to a photocopy machine.
File the petition in the family or juvenile court where the child resides. If in doubt you can call the clerk's office to ask where you should file the custody petition. There will be filing fees which vary. As of the publication date, for example, the filing fee for a custody petition is $90.38 in the first judicial district of Pennsylvania.
Once you file your petition, you will receive a stamped copy which you must serve on the natural parents and any appointed guardians via special process server such as the county sheriff. If your petition is based upon an emergency basis, there will be an accelerated hearing schedule and you may be immediately sent to a hearing.
Present your case at the hearing. If you filed for an emergency hearing, your petition may be heard immediately on an "ex parte" basis -- without the presence of the other parties -- where a court may enter a temporary order and then set a hearing date on a permanent change. Note that the court will need to hear of an immediate threat of harm to grant an emergency order.
For non-emergency petitions, the court will set a hearing if the parties cannot come to an agreement at a pre-trial. You will be able to present your testimony and witnesses to the judge, and the custodial parent will be allowed to contest your allegations. If the court finds that a modification is appropriate based upon the best interests of the child, it will enter an order of modification.