Age of Parents - Matter of practicality if there is a large age discrepancy 

Alcohol & Drug Use - Former and current use habits and any convictions or related problems 

Availability of Each Parent - Courts tend to favor a parent who has more time to spend with the children. If you are going through a divorce and want custody, it is important to spend as much time as possible with your children. The court will look to see who was the primary caretaker of the child. 

Financial Situation of Each Parent - Courts tend to favor a parent who can adequately provide for the children. It is important that you do not quit your job while trying to get custody. However, Courts can also impose Child Support Orders. 

Home Environment of Each Parent - Courts try to place children in a homes with safe and stable environments.

Disability, Mental, Emotional, & Physical Health - Relevant if it impacts how well the parent can care for children. Courts prefer an emotionally and mentally stable parent.

Siblings - Keeping siblings together is generally considered to be the best interest of the children but there are always exceptions. 

Marital Fault - In order to get a divorce in New York, the couple must demonstrate grounds. A court may evaluate If the event that spurred the divorce or separation endangered the children in any way.  

Relationship of parents - Courts try to place children with a parent that is willing to work with the other parent and encourage the relationship. Courts try to avoid awarding custody to a parent that tries to impede visitation or the child's relationship with the other parent.   

Preferences of the children - Children are not forced to choose one parent over the other. However, if the child does have a preference, the court will typically place more weight on the child's preference the closer a child is to age 18.  The court will also examine the reason for the preference and if that is in the best interest of the child.  

Law Guardian - The Law Guardian is an attorney assigned to represent the best interest of the children involved. This attorney is independent of either party. The law guardian may give the Court a recommendation on behalf of the children. 

Observable behavior - Behavior in court will be monitored closely and plays a significant factor in determining custody. Being argumentative or hostile should be avoided while being respectful, cooperative and reasonable is seen as more favorable. 

Previous Court Judgments - Prior cases of child abuse or neglect are significantly relevant to determine custody. Prior criminal or drug activity may also bode negatively for a parent. 

Collateral Sources - Relevant counselors, school officials, or other family members may be asked their opinions as to which parent should have custody.

Voluntary Custody Agreements - An attorney could help you negotiate an agreement with the other parent. The court assumes that no reasonable parent would voluntarily not act in the best interest of the children. Therefore, unless there is some compelling reason, the court will honor this agreement.