Chain of Command

What exactly is 'Chain of Command'?
Chain of Command dictates who is in charge, it is a power structure. All Heads of Staff are considered on an equal level apart from the captain who was authority over all crew. When being given orders they should be treated using the following priority as a crew member in a department:

The Captain > Your Head of Staff > Other Heads of Staff.

Refer to this image for power structure, it will assist you:



Interim Heads of Staff
In the event that a department is lacking a Head of Staff, someone with enough training can be assigned as a Interim Head of Staff by the Captain, Acting Captain, or the Head of Personnel.

Appointing an Acting Captain
An Acting Captain can be appointed by majority of command. Usually, appointing an Acting Captain is done in Code Red. The acting captain acts as if they have ultimate authority (including the ability to appoint interims as an interim captain themselves) abroad the station until an emergency concludes.

Missing Head of Staff
Chain of command works a lot like line/lane leading, you may will often jump in to fill in for giving directions in place where some heads of staff don't exist. You may need to provide leadership, giving directions, and helping out wherever necessary. You could also appoint an Interim Head of Staff to manage their own department due to their vast knowledge and experience in their respective department. For example, there is no CMO but there is an otherwise filled medical staff, you would take leadership and do the best you can help or you may appoint a qualified medical personnel to Interim Chief Medical Officer to manage the Medical Department.