System rules are a code of conduct that every insider must abide by.  These are sometimes confused with a Safety Contract.  A safety contract keeps the body safe, whereas system rules prevent bad behavior that would be socially disastrous or illegal.  System rules can and should include both aspects.  Where there are rules, there must be an enforcement of the rules, which means consequences.  Everyone must sign it and agree, and you must decide what consequences to have, such as no time out in the body, no video games, no spending money, inside grounding, etc.  You can have it "witnessed" and signed by your therapist if that makes everyone feel better or carries more weight.

Add to this list all rules that apply to you.

1. Kids stay away from messy things, like paint, dyes, or glue unless an adult is present and aware of what is going on, and consenting.
2. Only a responsible adult takes the medicine.  If a kid is out when meds need to be taken, they must get an adult to take it.
3. Do not self-injure or commit suicide.  If thoughts and desire of those things grow or cannot be withstood, call a knowing friend or therapist or local crisis line to talk it out.
4. Only adults can cook food.  Kids stay away from the stove and/or open flame, and knives.
5. Keep doors locked.  Do not let anyone in unless you or an adult inside knows them and they are safe.
6. Do not leave the house without all your clothes on.
7. Write down any questions or thoughts you want addressed in a notebook set aside for system communication (if you are not co-conscious).
8. Do not spend money unless everyone agrees that it is OK.
9. Do not tell anyone online where you live, your phone number, where you work, or any other identifying information, even if they promise to send you money.
10. Nobody can hurt someone else inside the system, or outside.  Hurt can be defined as physical, mental, sexual, or emotional.
11. Do not answer the phone unless given permission by the one(s) in charge.
12. If someone online shows unusual interest of inside children, cut all contact from that person, no matter how nice they seem.  Many predators, especially women, seek to make inside kids emotionally dependent on them.
13. Only the practice of [insert religious preferences here (such as Christian, Buddhism, etc.)] is permitted.
14. You may only talk to [insert names of people you trust that know you are MPD here] and no one else.
15. ...and so on.

Another Example