As in any real-life military, it's important to follow the chain of command in STF. This goes for both IC and OOC incidents. The low men on a ship's totem pole are the junior officers (Eng, Med, Sci, Sec, etc.) Next up are the DHs, then XO, and CO. If you're playing a cadet, he's answerable to his DH. Civilians typically work directly under the CO and/or XO.

What this boils down to is that your engineering ensign isn't going to be giving orders to anyone. The CE can order his engineers around all he wants. And the captain has your very soul in his hands. Of course, this is the enlightened 24th century, so it's not that bad. Ensigns are encouraged to give ideas, and captains don't make it a habit to sell their crews' souls to Satan.

The chain of command also extends beyond the ship. However, this extension only comes into play in OOC situations. Our roleplaying may be in the enlightened 24th century, but the players still live in the dog-eat-dog 21st century. Flaring egos, misunderstandings, and disagreements are bound to happen. And sometimes, you need help solving a problem.

Ideally, you should first try to work out the problem yourself. If that doesn't work, go to your CO. If you need to go beyond the CO, your next step is the FComm. Usually, that's as high as you ever need to go. But some problems can be persistent. After the FComm, you can go to either the appropriate cabinet director or directly to the president. For instance, if your problem involves a GM and the FComm can't/won't help, then you would go to the GM Director before the president.