In general, children traveling without their parents in the United States do not require the parents' written permission. It can still be a good idea to provide "permission to travel" documents for minor children however. Custody agreements sometimes restrict the right to travel, while many foreign countries have stringent requirements on documentation for adults traveling with minors who are not their children. In addition, your child might need identification and a medical consent form.

Identification

Children under 18 are not required to carry identification when traveling domestically, even when undergoing airport security screening by the Transportation Security Administration, or TSA. Nonetheless, older teens who look 18 might be questioned by the TSA, while children who qualify for a lower fare on an airline, train or other transportation might need to prove their age. Have your teen carry a school ID, a driver’s license or another form of photo identification. Give the trip leader a copy of your younger child’s birth certificate. For international flights, all travelers including infants must present a valid passport.

In the United States, children do not usually need to carry a written consent to travel. If the courts are involved in the child’s life, there may be orders restricting his ability to travel without permission of one or both parents. Some custody agreements forbid one or both parents from authorizing vacations without the other parent’s consent. Likewise, foster children must get permission to travel from their caseworker or social worker.

If your child will travel internationally, both parents should sign a notarized consent to travel. You can download a form online or create your own. Specify the child’s full name and address, the names and addresses of both parents, the names and addresses of the adults traveling with the child, the authorized destination countries and the dates of the trip. If you have sole custody, provide a copy of the relevant paperwork such as a death certificate or court order.

A medical consent form gives the accompanying adult the right to authorize medical treatment for your child while he is away. Some people combine a medical consent form with a general consent to travel form. Although it is not necessary, you might want to specify whether the accompanying adult is authorized to consent to elective procedures, such as plastic surgery. Enclose a copy of the front and back of the child’s medical insurance card.

Temporary Power of Attorney

If the trip will include activities such as parasailing or dog sledding that require parental consent, consider signing a temporary power of attorney. This is a legal document that gives the child’s adult travel companion the right to make virtually all parenting decisions for the specified period of time. A temporary power of attorney must be notarized.