An emergency contact list is one of those "just in case" things you don't want to have to use, but you should have ready and updated. Readily available contact information can be a lifesaver in the event of a medical emergency. The names of all the people you would want contacted should be listed, together with their phone numbers and their relationship to you or your family members. In an emergency situation even a person with the best of memories may not remember critical phone numbers. You or the medical staff may need to contact family members, and if you find yourself in a medical facility that doesn't allow cell phones in the building, then you won't have your handy address book available.
Your emergency list should include anyone who needs to be notified. This list shouldn't be limited to family members. Your list should include contact information for your home, your office or any other family member's workplace. Make sure you have school phone numbers and contacts as well. List people you may need to contact to take on certain responsibilities for you, such as picking up children from school or a babysitter. Friends, neighbors and relatives may be included, as well as pet-sitters if relevant. Every family has its own set of important contacts that they would need to call, and it's always better to prepare in advance.
Other important information to list would be scheduling items that your emergency contact people may need to know. This would include after-school activities such as play dates and any pending appointments. Your emergency contact list is just one of several items that need to be in the family emergency kit. In the event of an emergency, you should have family members assigned to make the necessary phone calls.