The typical minor consists of a minimum of 16-20 credits (4 or 5 courses). It may be part of your concentration. It may not. It really is up to you. Before you declare, be sure to chat with your adviser about where it fits into your program here at Gallatin.
You should be reminded that the addition of a minor in no way changes any of your obligations as a Gallatin student. You still need to formulate your concentration, write an IAPC, write a rationale, and complete your colloquium. Also, be aware that a minor becomes part of your graduation requirements (unless you opt to drop, which we discuss below).
It is really up to you, declaring a minor is not a Gallatin requirement. If you choose to declare a minor you should schedule an appointment with your faculty adviser to discuss the advantages and disadvantages of particular minors that might complement or extend your Gallatin concentration.
The department/school offering the minor determines the credit and course requirements. Gallatin has no standing in this process. Students must consult with the department/school offering the minor about course requirements and course substitution. (If you are approved to substitute a course, be sure to follow up with the department to ensure that they make the necessary changes to your record, i.e., degree requirements) In general you should use the Degree Progress on Albert to keep track of your minor and overall academic progress.