After 5 years, she can apply for permanent residency (C permit), assuming she meets all the requirements. She can also apply for facilitated naturalization at that time, assuming you were Swiss at the time of marriage (does not work if you obtained citizenship after the marriage).
If you are Swiss and the marriage is stable with no intent to separate or divorce, then a lot of this is formality and you should not worry too much. Your spouse receives a B permit with permission to work, and that permit needs to be renewed annually.